From c8ea0c12d755bb7f6217c8aebc7f5b8e391c1f89 Mon Sep 17 00:00:00 2001
From: Shamim Rezaie <shamim@moodle.com>
Date: Thu, 17 Sep 2020 01:12:54 +1000
Subject: [PATCH] MDL-69301 core: Enhanced WAI-ARIA support for tab elements

---
 lib/templates/settings_link_page.mustache     |  4 +-
 theme/boost/amd/build/aria.min.js             |  2 +-
 theme/boost/amd/build/aria.min.js.map         |  2 +-
 theme/boost/amd/build/loader.min.js           |  2 +-
 theme/boost/amd/build/loader.min.js.map       |  2 +-
 theme/boost/amd/src/aria.js                   | 82 ++++++++++++++++++-
 theme/boost/amd/src/loader.js                 | 13 +--
 .../templates/admin_setting_tabs.mustache     |  4 +-
 8 files changed, 98 insertions(+), 13 deletions(-)

diff --git a/lib/templates/settings_link_page.mustache b/lib/templates/settings_link_page.mustache
index 29917537fdc..07f07059992 100644
--- a/lib/templates/settings_link_page.mustache
+++ b/lib/templates/settings_link_page.mustache
@@ -40,7 +40,7 @@
 <ul class="nav nav-tabs" role="tablist">
 <!-- First the top most node and immediate children -->
     <li class="nav-item">
-        <a class="nav-link active" href="#link{{node.key}}" data-toggle="tab" role="tab">{{node.text}}</a>
+        <a class="nav-link active" href="#link{{node.key}}" data-toggle="tab" role="tab" aria-selected="true">{{node.text}}</a>
     </li>
 <!-- Now the first level children with sub nodes -->
 {{#node.children}}
@@ -48,7 +48,7 @@
         {{#display}}
             {{^is_short_branch}}
                 <li class="nav-item">
-                    <a class="nav-link" href="#link{{key}}" data-toggle="tab" role="tab">{{text}}</a>
+                    <a class="nav-link" href="#link{{key}}" data-toggle="tab" role="tab" aria-selected="false" tabindex="-1">{{text}}</a>
                 </li>
             {{/is_short_branch}}
         {{/display}}
diff --git a/theme/boost/amd/build/aria.min.js b/theme/boost/amd/build/aria.min.js
index e266186de4e..2265ffa34e3 100644
--- a/theme/boost/amd/build/aria.min.js
+++ b/theme/boost/amd/build/aria.min.js
@@ -1,2 +1,2 @@
-define ("theme_boost/aria",["exports","core/key_codes","jquery","core/pending"],function(a,b,c,d){"use strict";Object.defineProperty(a,"__esModule",{value:!0});a.init=void 0;c=e(c);d=e(d);function e(a){return a&&a.__esModule?a:{default:a}}var f=function(){var a=!1,e=function(){a=!0},f=function(){var b=a;a=!1;return b};document.addEventListener("keydown",function(a){if(a.target.matches("[data-toggle=\"dropdown\"]")){var c=a.which;if(c==b.arrowUp){e()}if(c==b.escape){var d=a.target.getAttribute("aria-expanded");a.preventDefault();if("false"==d){a.target.click()}}if(c==b.space||c==b.enter){a.preventDefault();a.target.click()}}});var g=function(a){setTimeout(function delayedFocus(b){a.focus();b.resolve()},50,new d.default("core/aria:delayed-focus"))};(0,c.default)(".dropdown").on("shown.bs.dropdown",function(a){var b=a.target.querySelector("[role=\"menu\"]"),c=!1,d=!1;if(b){c=b.querySelectorAll("[role=\"menuitem\"]")}if(c&&0<c.length){if(f()){d=c[c.length-1]}else{d=c[0]}}if(d){g(d)}});document.addEventListener("keypress",function(a){if(a.target.matches(".dropdown [role=\"menu\"] [role=\"menuitem\"]")){var b=String.fromCharCode(a.which).toLowerCase(),c=a.target.closest("[role=\"menu\"]");if(!c){return}var f=c.querySelectorAll("[role=\"menuitem\"]");if(!f){return}for(var h=0;h<f.length;h++){var d=f[h],e=d.text.trim().toLowerCase();if(0==e.indexOf(b)){g(d);break}}}});document.addEventListener("keydown",function(a){if(a.target.matches(".dropdown [role=\"menu\"] [role=\"menuitem\"]")){var c=a.which,d=!1,e=a.target.closest("[role=\"menu\"]");if(!e){return}var f=e.querySelectorAll("[role=\"menuitem\"]");if(!f){return}if(c==b.arrowDown){for(var h=0;h<f.length-1;h++){if(f[h]==a.target){d=f[h+1];break}}if(!d){d=f[0]}}else if(c==b.arrowUp){for(var i=1;i<f.length;i++){if(f[i]==a.target){d=f[i-1];break}}if(!d){d=f[f.length-1]}}else if(c==b.home){d=f[0]}else if(c==b.end){d=f[f.length-1]}if(d){a.preventDefault();g(d)}}});(0,c.default)(".dropdown").on("hidden.bs.dropdown",function(a){var b=a.target.querySelector("[data-toggle=\"dropdown\"]");if(b){g(b)}})},g=function(){window.addEventListener("load",function(){var a=document.querySelectorAll("[data-aria-autofocus=\"true\"][role=\"alert\"]");Array.prototype.forEach.call(a,function(a){a.innerHTML+=" ";a.removeAttribute("data-aria-autofocus")})})};a.init=function init(){f();g()}});
+define ("theme_boost/aria",["exports","core/key_codes","jquery","core/pending"],function(a,b,c,d){"use strict";Object.defineProperty(a,"__esModule",{value:!0});a.init=void 0;c=e(c);d=e(d);function e(a){return a&&a.__esModule?a:{default:a}}var f=function(){var a=!1,e=function(){a=!0},f=function(){var b=a;a=!1;return b};document.addEventListener("keydown",function(a){if(a.target.matches("[data-toggle=\"dropdown\"]")){var c=a.which;if(c==b.arrowUp){e()}if(c==b.escape){var d=a.target.getAttribute("aria-expanded");a.preventDefault();if("false"==d){a.target.click()}}if(c==b.space||c==b.enter){a.preventDefault();a.target.click()}}});var g=function(a){setTimeout(function delayedFocus(b){a.focus();b.resolve()},50,new d.default("core/aria:delayed-focus"))};(0,c.default)(".dropdown").on("shown.bs.dropdown",function(a){var b=a.target.querySelector("[role=\"menu\"]"),c=!1,d=!1;if(b){c=b.querySelectorAll("[role=\"menuitem\"]")}if(c&&0<c.length){if(f()){d=c[c.length-1]}else{d=c[0]}}if(d){g(d)}});document.addEventListener("keypress",function(a){if(a.target.matches(".dropdown [role=\"menu\"] [role=\"menuitem\"]")){var b=String.fromCharCode(a.which).toLowerCase(),c=a.target.closest("[role=\"menu\"]");if(!c){return}var f=c.querySelectorAll("[role=\"menuitem\"]");if(!f){return}for(var h=0;h<f.length;h++){var d=f[h],e=d.text.trim().toLowerCase();if(0==e.indexOf(b)){g(d);break}}}});document.addEventListener("keydown",function(a){if(a.target.matches(".dropdown [role=\"menu\"] [role=\"menuitem\"]")){var c=a.which,d=!1,e=a.target.closest("[role=\"menu\"]");if(!e){return}var f=e.querySelectorAll("[role=\"menuitem\"]");if(!f){return}if(c==b.arrowDown){for(var h=0;h<f.length-1;h++){if(f[h]==a.target){d=f[h+1];break}}if(!d){d=f[0]}}else if(c==b.arrowUp){for(var i=1;i<f.length;i++){if(f[i]==a.target){d=f[i-1];break}}if(!d){d=f[f.length-1]}}else if(c==b.home){d=f[0]}else if(c==b.end){d=f[f.length-1]}if(d){a.preventDefault();g(d)}}});(0,c.default)(".dropdown").on("hidden.bs.dropdown",function(a){var b=a.target.querySelector("[data-toggle=\"dropdown\"]");if(b){g(b)}})},g=function(){window.addEventListener("load",function(){var a=document.querySelectorAll("[data-aria-autofocus=\"true\"][role=\"alert\"]");Array.prototype.forEach.call(a,function(a){a.innerHTML+=" ";a.removeAttribute("data-aria-autofocus")})})},h=function(a){for(var d=a.target.closest("[role=\"tablist\"]"),e="vertical"==d.getAttribute("aria-orientation"),f=window.right_to_left(),g=e?b.arrowDown:f?b.arrowLeft:b.arrowRight,h=e?b.arrowUp:f?b.arrowRight:b.arrowLeft,j=Array.prototype.filter.call(d.querySelectorAll("[role=\"tab\"]"),function(a){return"none"!==getComputedStyle(a).display}),k=0;k<j.length;k++){j[k].index=k}switch(a.keyCode){case g:a.preventDefault();if(a.target.index!==void 0&&j[a.target.index+1]){j[a.target.index+1].focus()}else{j[0].focus()}break;case h:a.preventDefault();if(a.target.index!==void 0&&j[a.target.index-1]){j[a.target.index-1].focus()}else{j[j.length-1].focus()}break;case b.home:a.preventDefault();j[0].focus();break;case b.end:a.preventDefault();j[j.length-1].focus();break;case b.enter:case b.space:a.preventDefault();(0,c.default)(a.target).tab("show");j.forEach(function(a){a.tabIndex=-1});a.target.tabIndex=0;}},i=function(){document.addEventListener("keydown",function(a){if([b.arrowUp,b.arrowDown,b.arrowLeft,b.arrowRight,b.home,b.end,b.enter,b.space].includes(a.keyCode)){if(a.target.matches("[role=\"tablist\"] [role=\"tab\"]")){h(a)}}});document.addEventListener("click",function(a){if(a.target.matches("[role=\"tablist\"] [role=\"tab\"]")){var b=a.target.closest("[role=\"tablist\"]").querySelectorAll("[role=\"tab\"]");a.preventDefault();(0,c.default)(a.target).tab("show");b.forEach(function(a){a.tabIndex=-1});a.target.tabIndex=0}})};a.init=function init(){f();g();i()}});
 //# sourceMappingURL=aria.min.js.map
diff --git a/theme/boost/amd/build/aria.min.js.map b/theme/boost/amd/build/aria.min.js.map
index 509f86887b4..72602e53be7 100644
--- a/theme/boost/amd/build/aria.min.js.map
+++ b/theme/boost/amd/build/aria.min.js.map
@@ -1 +1 @@
-{"version":3,"sources":["../src/aria.js"],"names":["dropdownFix","focusEnd","setFocusEnd","getFocusEnd","result","document","addEventListener","e","target","matches","trigger","which","arrowUp","escape","expanded","getAttribute","preventDefault","click","space","enter","shiftFocus","element","setTimeout","delayedFocus","pendingPromise","focus","resolve","Pending","on","menu","querySelector","menuItems","foundMenuItem","querySelectorAll","length","String","fromCharCode","toLowerCase","closest","i","item","itemText","text","trim","indexOf","next","arrowDown","home","end","autoFocus","window","alerts","Array","prototype","forEach","call","autofocusElement","innerHTML","removeAttribute","init"],"mappings":"8KAwBA,OACA,O,sDAKMA,CAAAA,CAAW,CAAG,UAAM,IAClBC,CAAAA,CAAQ,GADU,CAEhBC,CAAW,CAAG,UAAM,CACtBD,CAAQ,GACX,CAJqB,CAKhBE,CAAW,CAAG,UAAM,CACtB,GAAMC,CAAAA,CAAM,CAAGH,CAAf,CACAA,CAAQ,GAAR,CACA,MAAOG,CAAAA,CACV,CATqB,CAYtBC,QAAQ,CAACC,gBAAT,CAA0B,SAA1B,CAAqC,SAAAC,CAAC,CAAI,CACtC,GAAIA,CAAC,CAACC,MAAF,CAASC,OAAT,CAAiB,4BAAjB,CAAJ,CAAkD,CAC9C,GAAMC,CAAAA,CAAO,CAAGH,CAAC,CAACI,KAAlB,CAGA,GAAID,CAAO,EAAIE,SAAf,CAAwB,CAEpBV,CAAW,EACd,CAGD,GAAIQ,CAAO,EAAIG,QAAf,CAAuB,CACnB,GAAMC,CAAAA,CAAQ,CAAGP,CAAC,CAACC,MAAF,CAASO,YAAT,CAAsB,eAAtB,CAAjB,CACAR,CAAC,CAACS,cAAF,GACA,GAAgB,OAAZ,EAAAF,CAAJ,CAAyB,CACrBP,CAAC,CAACC,MAAF,CAASS,KAAT,EACH,CACJ,CAGD,GAAIP,CAAO,EAAIQ,OAAX,EAAoBR,CAAO,EAAIS,OAAnC,CAA0C,CAEtCZ,CAAC,CAACS,cAAF,GAEAT,CAAC,CAACC,MAAF,CAASS,KAAT,EACH,CACJ,CACJ,CA3BD,EA8BA,GAAMG,CAAAA,CAAU,CAAG,SAAAC,CAAO,CAAI,CAK1BC,UAAU,CAJW,QAAfC,CAAAA,YAAe,CAAAC,CAAc,CAAI,CACnCH,CAAO,CAACI,KAAR,GACAD,CAAc,CAACE,OAAf,EACH,CACS,CAAe,EAAf,CAAmB,GAAIC,UAAJ,CAAY,yBAAZ,CAAnB,CACb,CAND,CAQA,cAAE,WAAF,EAAeC,EAAf,CAAkB,mBAAlB,CAAuC,SAAArB,CAAC,CAAI,IAElCsB,CAAAA,CAAI,CAAGtB,CAAC,CAACC,MAAF,CAASsB,aAAT,CAAuB,iBAAvB,CAF2B,CAGpCC,CAAS,GAH2B,CAIpCC,CAAa,GAJuB,CAMxC,GAAIH,CAAJ,CAAU,CACNE,CAAS,CAAGF,CAAI,CAACI,gBAAL,CAAsB,qBAAtB,CACf,CACD,GAAIF,CAAS,EAAuB,CAAnB,CAAAA,CAAS,CAACG,MAA3B,CAAuC,CACnC,GAAI/B,CAAW,EAAf,CAAmB,CACf6B,CAAa,CAAGD,CAAS,CAACA,CAAS,CAACG,MAAV,CAAmB,CAApB,CAC5B,CAFD,IAEO,CAEHF,CAAa,CAAGD,CAAS,CAAC,CAAD,CAC5B,CACJ,CACD,GAAIC,CAAJ,CAAmB,CACfZ,CAAU,CAACY,CAAD,CACb,CACJ,CApBD,EAuBA3B,QAAQ,CAACC,gBAAT,CAA0B,UAA1B,CAAsC,SAAAC,CAAC,CAAI,CACvC,GAAIA,CAAC,CAACC,MAAF,CAASC,OAAT,CAAiB,+CAAjB,CAAJ,CAAmE,IACzDC,CAAAA,CAAO,CAAGyB,MAAM,CAACC,YAAP,CAAoB7B,CAAC,CAACI,KAAtB,EAA6B0B,WAA7B,EAD+C,CAEzDR,CAAI,CAAGtB,CAAC,CAACC,MAAF,CAAS8B,OAAT,CAAiB,iBAAjB,CAFkD,CAI/D,GAAI,CAACT,CAAL,CAAW,CACP,MACH,CACD,GAAME,CAAAA,CAAS,CAAGF,CAAI,CAACI,gBAAL,CAAsB,qBAAtB,CAAlB,CACA,GAAI,CAACF,CAAL,CAAgB,CACZ,MACH,CAED,IAAK,GAAIQ,CAAAA,CAAC,CAAG,CAAb,CAAgBA,CAAC,CAAGR,CAAS,CAACG,MAA9B,CAAsCK,CAAC,EAAvC,CAA2C,IACjCC,CAAAA,CAAI,CAAGT,CAAS,CAACQ,CAAD,CADiB,CAEjCE,CAAQ,CAAGD,CAAI,CAACE,IAAL,CAAUC,IAAV,GAAiBN,WAAjB,EAFsB,CAGvC,GAAiC,CAA7B,EAAAI,CAAQ,CAACG,OAAT,CAAiBlC,CAAjB,CAAJ,CAAoC,CAChCU,CAAU,CAACoB,CAAD,CAAV,CACA,KACH,CACJ,CACJ,CACJ,CAtBD,EAyBAnC,QAAQ,CAACC,gBAAT,CAA0B,SAA1B,CAAqC,SAAAC,CAAC,CAAI,CACtC,GAAIA,CAAC,CAACC,MAAF,CAASC,OAAT,CAAiB,+CAAjB,CAAJ,CAAmE,IACzDC,CAAAA,CAAO,CAAGH,CAAC,CAACI,KAD6C,CAE3DkC,CAAI,GAFuD,CAGzDhB,CAAI,CAAGtB,CAAC,CAACC,MAAF,CAAS8B,OAAT,CAAiB,iBAAjB,CAHkD,CAK/D,GAAI,CAACT,CAAL,CAAW,CACP,MACH,CACD,GAAME,CAAAA,CAAS,CAAGF,CAAI,CAACI,gBAAL,CAAsB,qBAAtB,CAAlB,CACA,GAAI,CAACF,CAAL,CAAgB,CACZ,MACH,CAED,GAAIrB,CAAO,EAAIoC,WAAf,CAA0B,CACtB,IAAK,GAAIP,CAAAA,CAAC,CAAG,CAAb,CAAgBA,CAAC,CAAGR,CAAS,CAACG,MAAV,CAAmB,CAAvC,CAA0CK,CAAC,EAA3C,CAA+C,CAC3C,GAAIR,CAAS,CAACQ,CAAD,CAAT,EAAgBhC,CAAC,CAACC,MAAtB,CAA8B,CAC1BqC,CAAI,CAAGd,CAAS,CAACQ,CAAC,CAAG,CAAL,CAAhB,CACA,KACH,CACJ,CACD,GAAI,CAACM,CAAL,CAAW,CAEPA,CAAI,CAAGd,CAAS,CAAC,CAAD,CACnB,CAEJ,CAZD,IAYO,IAAIrB,CAAO,EAAIE,SAAf,CAAwB,CAE3B,IAAK,GAAI2B,CAAAA,CAAC,CAAG,CAAb,CAAgBA,CAAC,CAAGR,CAAS,CAACG,MAA9B,CAAsCK,CAAC,EAAvC,CAA2C,CACvC,GAAIR,CAAS,CAACQ,CAAD,CAAT,EAAgBhC,CAAC,CAACC,MAAtB,CAA8B,CAC1BqC,CAAI,CAAGd,CAAS,CAACQ,CAAC,CAAG,CAAL,CAAhB,CACA,KACH,CACJ,CACD,GAAI,CAACM,CAAL,CAAW,CAEPA,CAAI,CAAGd,CAAS,CAACA,CAAS,CAACG,MAAV,CAAmB,CAApB,CACnB,CAEJ,CAbM,IAaA,IAAIxB,CAAO,EAAIqC,MAAf,CAAqB,CAExBF,CAAI,CAAGd,CAAS,CAAC,CAAD,CAEnB,CAJM,IAIA,IAAIrB,CAAO,EAAIsC,KAAf,CAAoB,CAEvBH,CAAI,CAAGd,CAAS,CAACA,CAAS,CAACG,MAAV,CAAmB,CAApB,CACnB,CAED,GAAIW,CAAJ,CAAU,CACNtC,CAAC,CAACS,cAAF,GACAI,CAAU,CAACyB,CAAD,CACb,CAEJ,CACJ,CAtDD,EAwDA,cAAE,WAAF,EAAejB,EAAf,CAAkB,oBAAlB,CAAwC,SAAArB,CAAC,CAAI,CAEzC,GAAMG,CAAAA,CAAO,CAAGH,CAAC,CAACC,MAAF,CAASsB,aAAT,CAAuB,4BAAvB,CAAhB,CACA,GAAIpB,CAAJ,CAAa,CACTU,CAAU,CAACV,CAAD,CACb,CACJ,CAND,CAOH,C,CAKKuC,CAAS,CAAG,UAAM,CACpBC,MAAM,CAAC5C,gBAAP,CAAwB,MAAxB,CAAgC,UAAM,CAClC,GAAM6C,CAAAA,CAAM,CAAG9C,QAAQ,CAAC4B,gBAAT,CAA0B,gDAA1B,CAAf,CACAmB,KAAK,CAACC,SAAN,CAAgBC,OAAhB,CAAwBC,IAAxB,CAA6BJ,CAA7B,CAAqC,SAAAK,CAAgB,CAAI,CAGrDA,CAAgB,CAACC,SAAjB,EAA8B,GAA9B,CACAD,CAAgB,CAACE,eAAjB,CAAiC,qBAAjC,CACH,CALD,CAMH,CARD,CASH,C,QAEmB,QAAPC,CAAAA,IAAO,EAAM,CACtB3D,CAAW,GACXiD,CAAS,EACZ,C","sourcesContent":["// This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n\n/**\n * Enhancements to Bootstrap components for accessibility.\n *\n * @module     theme_boost/aria\n * @copyright  2018 Damyon Wiese <damyon@moodle.com>\n * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n */\n\nimport {end, escape, arrowUp, arrowDown, home, enter, space} from 'core/key_codes';\nimport $ from 'jquery';\nimport Pending from 'core/pending';\n\n/**\n * Drop downs from bootstrap don't support keyboard accessibility by default.\n */\nconst dropdownFix = () => {\n    let focusEnd = false;\n    const setFocusEnd = () => {\n        focusEnd = true;\n    };\n    const getFocusEnd = () => {\n        const result = focusEnd;\n        focusEnd = false;\n        return result;\n    };\n\n    // Special handling for \"up\" keyboard control.\n    document.addEventListener('keydown', e => {\n        if (e.target.matches('[data-toggle=\"dropdown\"]')) {\n            const trigger = e.which;\n\n            // Up key opens the menu at the end.\n            if (trigger == arrowUp) {\n                // Focus the end of the menu, not the beginning.\n                setFocusEnd();\n            }\n\n            // Escape key only closes the menu, it doesn't open it.\n            if (trigger == escape) {\n                const expanded = e.target.getAttribute('aria-expanded');\n                e.preventDefault();\n                if (expanded == \"false\") {\n                    e.target.click();\n                }\n            }\n\n            // Space key or Enter key opens the menu.\n            if (trigger == space || trigger == enter) {\n                // Cancel random scroll.\n                e.preventDefault();\n                // Open the menu instead.\n                e.target.click();\n            }\n        }\n    });\n\n    // Special handling for navigation keys when menu is open.\n    const shiftFocus = element => {\n        const delayedFocus = pendingPromise => {\n            element.focus();\n            pendingPromise.resolve();\n        };\n        setTimeout(delayedFocus, 50, new Pending('core/aria:delayed-focus'));\n    };\n\n    $('.dropdown').on('shown.bs.dropdown', e => {\n        // We need to focus on the first menuitem.\n        const menu = e.target.querySelector('[role=\"menu\"]');\n        let menuItems = false;\n        let foundMenuItem = false;\n\n        if (menu) {\n            menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n        }\n        if (menuItems && menuItems.length > 0) {\n            if (getFocusEnd()) {\n                foundMenuItem = menuItems[menuItems.length - 1];\n            } else {\n                // The first menu entry, pretty reasonable.\n                foundMenuItem = menuItems[0];\n            }\n        }\n        if (foundMenuItem) {\n            shiftFocus(foundMenuItem);\n        }\n    });\n    // Search for menu items by finding the first item that has\n    // text starting with the typed character (case insensitive).\n    document.addEventListener('keypress', e => {\n        if (e.target.matches('.dropdown [role=\"menu\"] [role=\"menuitem\"]')) {\n            const trigger = String.fromCharCode(e.which).toLowerCase();\n            const menu = e.target.closest('[role=\"menu\"]');\n\n            if (!menu) {\n                return;\n            }\n            const menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n            if (!menuItems) {\n                return;\n            }\n\n            for (let i = 0; i < menuItems.length; i++) {\n                const item = menuItems[i];\n                const itemText = item.text.trim().toLowerCase();\n                if (itemText.indexOf(trigger) == 0) {\n                    shiftFocus(item);\n                    break;\n                }\n            }\n        }\n    });\n\n    // Keyboard navigation for arrow keys, home and end keys.\n    document.addEventListener('keydown', e => {\n        if (e.target.matches('.dropdown [role=\"menu\"] [role=\"menuitem\"]')) {\n            const trigger = e.which;\n            let next = false;\n            const menu = e.target.closest('[role=\"menu\"]');\n\n            if (!menu) {\n                return;\n            }\n            const menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n            if (!menuItems) {\n                return;\n            }\n            // Down key.\n            if (trigger == arrowDown) {\n                for (let i = 0; i < menuItems.length - 1; i++) {\n                    if (menuItems[i] == e.target) {\n                        next = menuItems[i + 1];\n                        break;\n                    }\n                }\n                if (!next) {\n                    // Wrap to first item.\n                    next = menuItems[0];\n                }\n\n            } else if (trigger == arrowUp) {\n                // Up key.\n                for (let i = 1; i < menuItems.length; i++) {\n                    if (menuItems[i] == e.target) {\n                        next = menuItems[i - 1];\n                        break;\n                    }\n                }\n                if (!next) {\n                    // Wrap to last item.\n                    next = menuItems[menuItems.length - 1];\n                }\n\n            } else if (trigger == home) {\n                // Home key.\n                next = menuItems[0];\n\n            } else if (trigger == end) {\n                // End key.\n                next = menuItems[menuItems.length - 1];\n            }\n            // Variable next is set if we do want to act on the keypress.\n            if (next) {\n                e.preventDefault();\n                shiftFocus(next);\n            }\n            return;\n        }\n    });\n\n    $('.dropdown').on('hidden.bs.dropdown', e => {\n        // We need to focus on the menu trigger.\n        const trigger = e.target.querySelector('[data-toggle=\"dropdown\"]');\n        if (trigger) {\n            shiftFocus(trigger);\n        }\n    });\n};\n\n/**\n * After page load, focus on any element with special autofocus attribute.\n */\nconst autoFocus = () => {\n    window.addEventListener(\"load\", () => {\n        const alerts = document.querySelectorAll('[data-aria-autofocus=\"true\"][role=\"alert\"]');\n        Array.prototype.forEach.call(alerts, autofocusElement => {\n            // According to the specification an role=\"alert\" region is only read out on change to the content\n            // of that region.\n            autofocusElement.innerHTML += ' ';\n            autofocusElement.removeAttribute('data-aria-autofocus');\n        });\n    });\n};\n\nexport const init = () => {\n    dropdownFix();\n    autoFocus();\n};\n"],"file":"aria.min.js"}
\ No newline at end of file
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This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n\n/**\n * Enhancements to Bootstrap components for accessibility.\n *\n * @module     theme_boost/aria\n * @copyright  2018 Damyon Wiese <damyon@moodle.com>\n * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n */\n\nimport {end, escape, arrowUp, arrowDown, arrowLeft, arrowRight, home, enter, space} from 'core/key_codes';\nimport $ from 'jquery';\nimport Pending from 'core/pending';\n\n/**\n * Drop downs from bootstrap don't support keyboard accessibility by default.\n */\nconst dropdownFix = () => {\n    let focusEnd = false;\n    const setFocusEnd = () => {\n        focusEnd = true;\n    };\n    const getFocusEnd = () => {\n        const result = focusEnd;\n        focusEnd = false;\n        return result;\n    };\n\n    // Special handling for \"up\" keyboard control.\n    document.addEventListener('keydown', e => {\n        if (e.target.matches('[data-toggle=\"dropdown\"]')) {\n            const trigger = e.which;\n\n            // Up key opens the menu at the end.\n            if (trigger == arrowUp) {\n                // Focus the end of the menu, not the beginning.\n                setFocusEnd();\n            }\n\n            // Escape key only closes the menu, it doesn't open it.\n            if (trigger == escape) {\n                const expanded = e.target.getAttribute('aria-expanded');\n                e.preventDefault();\n                if (expanded == \"false\") {\n                    e.target.click();\n                }\n            }\n\n            // Space key or Enter key opens the menu.\n            if (trigger == space || trigger == enter) {\n                // Cancel random scroll.\n                e.preventDefault();\n                // Open the menu instead.\n                e.target.click();\n            }\n        }\n    });\n\n    // Special handling for navigation keys when menu is open.\n    const shiftFocus = element => {\n        const delayedFocus = pendingPromise => {\n            element.focus();\n            pendingPromise.resolve();\n        };\n        setTimeout(delayedFocus, 50, new Pending('core/aria:delayed-focus'));\n    };\n\n    $('.dropdown').on('shown.bs.dropdown', e => {\n        // We need to focus on the first menuitem.\n        const menu = e.target.querySelector('[role=\"menu\"]');\n        let menuItems = false;\n        let foundMenuItem = false;\n\n        if (menu) {\n            menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n        }\n        if (menuItems && menuItems.length > 0) {\n            if (getFocusEnd()) {\n                foundMenuItem = menuItems[menuItems.length - 1];\n            } else {\n                // The first menu entry, pretty reasonable.\n                foundMenuItem = menuItems[0];\n            }\n        }\n        if (foundMenuItem) {\n            shiftFocus(foundMenuItem);\n        }\n    });\n    // Search for menu items by finding the first item that has\n    // text starting with the typed character (case insensitive).\n    document.addEventListener('keypress', e => {\n        if (e.target.matches('.dropdown [role=\"menu\"] [role=\"menuitem\"]')) {\n            const trigger = String.fromCharCode(e.which).toLowerCase();\n            const menu = e.target.closest('[role=\"menu\"]');\n\n            if (!menu) {\n                return;\n            }\n            const menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n            if (!menuItems) {\n                return;\n            }\n\n            for (let i = 0; i < menuItems.length; i++) {\n                const item = menuItems[i];\n                const itemText = item.text.trim().toLowerCase();\n                if (itemText.indexOf(trigger) == 0) {\n                    shiftFocus(item);\n                    break;\n                }\n            }\n        }\n    });\n\n    // Keyboard navigation for arrow keys, home and end keys.\n    document.addEventListener('keydown', e => {\n        if (e.target.matches('.dropdown [role=\"menu\"] [role=\"menuitem\"]')) {\n            const trigger = e.which;\n            let next = false;\n            const menu = e.target.closest('[role=\"menu\"]');\n\n            if (!menu) {\n                return;\n            }\n            const menuItems = menu.querySelectorAll('[role=\"menuitem\"]');\n            if (!menuItems) {\n                return;\n            }\n            // Down key.\n            if (trigger == arrowDown) {\n                for (let i = 0; i < menuItems.length - 1; i++) {\n                    if (menuItems[i] == e.target) {\n                        next = menuItems[i + 1];\n                        break;\n                    }\n                }\n                if (!next) {\n                    // Wrap to first item.\n                    next = menuItems[0];\n                }\n\n            } else if (trigger == arrowUp) {\n                // Up key.\n                for (let i = 1; i < menuItems.length; i++) {\n                    if (menuItems[i] == e.target) {\n                        next = menuItems[i - 1];\n                        break;\n                    }\n                }\n                if (!next) {\n                    // Wrap to last item.\n                    next = menuItems[menuItems.length - 1];\n                }\n\n            } else if (trigger == home) {\n                // Home key.\n                next = menuItems[0];\n\n            } else if (trigger == end) {\n                // End key.\n                next = menuItems[menuItems.length - 1];\n            }\n            // Variable next is set if we do want to act on the keypress.\n            if (next) {\n                e.preventDefault();\n                shiftFocus(next);\n            }\n            return;\n        }\n    });\n\n    $('.dropdown').on('hidden.bs.dropdown', e => {\n        // We need to focus on the menu trigger.\n        const trigger = e.target.querySelector('[data-toggle=\"dropdown\"]');\n        if (trigger) {\n            shiftFocus(trigger);\n        }\n    });\n};\n\n/**\n * After page load, focus on any element with special autofocus attribute.\n */\nconst autoFocus = () => {\n    window.addEventListener(\"load\", () => {\n        const alerts = document.querySelectorAll('[data-aria-autofocus=\"true\"][role=\"alert\"]');\n        Array.prototype.forEach.call(alerts, autofocusElement => {\n            // According to the specification an role=\"alert\" region is only read out on change to the content\n            // of that region.\n            autofocusElement.innerHTML += ' ';\n            autofocusElement.removeAttribute('data-aria-autofocus');\n        });\n    });\n};\n\n/**\n * Changes the focus to the correct tab based on the key that is pressed.\n * @param {KeyboardEvent} e\n */\nconst updateTabFocus = e => {\n    const tabList = e.target.closest('[role=\"tablist\"]');\n    const vertical = tabList.getAttribute('aria-orientation') == 'vertical';\n    const rtl = window.right_to_left();\n    const arrowNext = vertical ? arrowDown : (rtl ? arrowLeft : arrowRight);\n    const arrowPrevious = vertical ? arrowUp : (rtl ? arrowRight : arrowLeft);\n    const tabs = Array.prototype.filter.call(\n        tabList.querySelectorAll('[role=\"tab\"]'),\n        tab => getComputedStyle(tab).display !== 'none'); // We only work with the visible tabs.\n\n    for (let i = 0; i < tabs.length; i++) {\n        tabs[i].index = i;\n    }\n\n    switch (e.keyCode) {\n        case arrowNext:\n            e.preventDefault();\n            if (e.target.index !== undefined && tabs[e.target.index + 1]) {\n                tabs[e.target.index + 1].focus();\n            } else {\n                tabs[0].focus();\n            }\n            break;\n        case arrowPrevious:\n            e.preventDefault();\n            if (e.target.index !== undefined && tabs[e.target.index - 1]) {\n                tabs[e.target.index - 1].focus();\n            } else {\n                tabs[tabs.length - 1].focus();\n            }\n            break;\n        case home:\n            e.preventDefault();\n            tabs[0].focus();\n            break;\n        case end:\n            e.preventDefault();\n            tabs[tabs.length - 1].focus();\n            break;\n        case enter:\n        case space:\n            e.preventDefault();\n            $(e.target).tab('show');\n            tabs.forEach(tab => {\n                tab.tabIndex = -1;\n            });\n            e.target.tabIndex = 0;\n    }\n};\n\n/**\n * Fix accessibility issues regarding tab elements focus and their tab order in Bootstrap navs.\n */\nconst tabElementFix = () => {\n    document.addEventListener('keydown', e => {\n        if ([arrowUp, arrowDown, arrowLeft, arrowRight, home, end, enter, space].includes(e.keyCode)) {\n            if (e.target.matches('[role=\"tablist\"] [role=\"tab\"]')) {\n                updateTabFocus(e);\n            }\n        }\n    });\n\n    document.addEventListener('click', e => {\n        if (e.target.matches('[role=\"tablist\"] [role=\"tab\"]')) {\n            const tabs = e.target.closest('[role=\"tablist\"]').querySelectorAll('[role=\"tab\"]');\n            e.preventDefault();\n            $(e.target).tab('show');\n            tabs.forEach(tab => {\n                tab.tabIndex = -1;\n            });\n            e.target.tabIndex = 0;\n        }\n    });\n};\n\nexport const init = () => {\n    dropdownFix();\n    autoFocus();\n    tabElementFix();\n};\n"],"file":"aria.min.js"}
\ No newline at end of file
diff --git a/theme/boost/amd/build/loader.min.js b/theme/boost/amd/build/loader.min.js
index 188f865c930..4f9b80475c2 100644
--- a/theme/boost/amd/build/loader.min.js
+++ b/theme/boost/amd/build/loader.min.js
@@ -1,2 +1,2 @@
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diff --git a/theme/boost/amd/build/loader.min.js.map b/theme/boost/amd/build/loader.min.js.map
index 63d1fc7f7c7..f9e4a1b19d0 100644
--- a/theme/boost/amd/build/loader.min.js.map
+++ b/theme/boost/amd/build/loader.min.js.map
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\ No newline at end of file
+{"version":3,"sources":["../src/loader.js"],"names":["rememberTabs","on","e","hash","target","attr","history","replaceState","location","window","tab","document","querySelector","click","enablePopovers","popover","container","selector","trigger","addEventListener","key","closest","enableTooltips","tooltip","pendingPromise","Pending","Aria","init","Scroll","$","fn","dropdown","Constructor","Default","flip","resolve"],"mappings":"wkBA0BA,OACA,OACA,OACA,OACA,OACA,O,4lBAKMA,CAAAA,CAAY,CAAG,UAAM,CACvB,cAAE,wBAAF,EAA0BC,EAA1B,CAA6B,cAA7B,CAA6C,SAASC,CAAT,CAAY,CACrD,GAAIC,CAAAA,CAAI,CAAG,cAAED,CAAC,CAACE,MAAJ,EAAYC,IAAZ,CAAiB,MAAjB,CAAX,CACA,GAAIC,OAAO,CAACC,YAAZ,CAA0B,CACtBD,OAAO,CAACC,YAAR,CAAqB,IAArB,CAA2B,IAA3B,CAAiCJ,CAAjC,CACH,CAFD,IAEO,CACHK,QAAQ,CAACL,IAAT,CAAgBA,CACnB,CACJ,CAPD,EAQA,GAAMA,CAAAA,CAAI,CAAGM,MAAM,CAACD,QAAP,CAAgBL,IAA7B,CACA,GAAIA,CAAJ,CAAU,CACN,GAAMO,CAAAA,CAAG,CAAGC,QAAQ,CAACC,aAAT,CAAuB,oBAAqBT,CAArB,CAA4B,KAAnD,CAAZ,CACA,GAAIO,CAAJ,CAAS,CACLA,CAAG,CAACG,KAAJ,EACH,CACJ,CACJ,C,CAMKC,CAAc,CAAG,UAAM,CACzB,cAAE,MAAF,EAAUC,OAAV,CAAkB,CACdC,SAAS,CAAE,MADG,CAEdC,QAAQ,CAAE,2BAFI,CAGdC,OAAO,CAAE,OAHK,CAAlB,EAMAP,QAAQ,CAACQ,gBAAT,CAA0B,SAA1B,CAAqC,SAAAjB,CAAC,CAAI,CACtC,GAAc,QAAV,GAAAA,CAAC,CAACkB,GAAF,EAAsBlB,CAAC,CAACE,MAAF,CAASiB,OAAT,CAAiB,2BAAjB,CAA1B,CAAuE,CACnE,cAAEnB,CAAC,CAACE,MAAJ,EAAYW,OAAZ,CAAoB,MAApB,CACH,CACJ,CAJD,CAKH,C,CAMKO,CAAc,CAAG,UAAM,CACzB,cAAE,MAAF,EAAUC,OAAV,CAAkB,CACdP,SAAS,CAAE,MADG,CAEdC,QAAQ,CAAE,2BAFI,CAAlB,CAIH,C,CAEKO,CAAc,CAAG,GAAIC,UAAJ,CAAY,yBAAZ,C,CAGvB,gBAGAC,CAAI,CAACC,IAAL,GAGA3B,CAAY,GAGZc,CAAc,GAGdQ,CAAc,GAGb,GAAIM,UAAJ,EAAD,CAAeD,IAAf,GAGAE,UAAEC,EAAF,CAAKC,QAAL,CAAcC,WAAd,CAA0BC,OAA1B,CAAkCC,IAAlC,IAEAV,CAAc,CAACW,OAAf,E","sourcesContent":["// This file is part of Moodle - http://moodle.org/\n//\n// Moodle is free software: you can redistribute it and/or modify\n// it under the terms of the GNU General Public License as published by\n// the Free Software Foundation, either version 3 of the License, or\n// (at your option) any later version.\n//\n// Moodle is distributed in the hope that it will be useful,\n// but WITHOUT ANY WARRANTY; without even the implied warranty of\n// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n// GNU General Public License for more details.\n//\n// You should have received a copy of the GNU General Public License\n// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.\n\n/**\n * Template renderer for Moodle. Load and render Moodle templates with Mustache.\n *\n * @module     core/templates\n * @package    core\n * @class      templates\n * @copyright  2015 Damyon Wiese <damyon@moodle.com>\n * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later\n * @since      2.9\n */\n\nimport $ from 'jquery';\nimport * as Aria from './aria';\nimport Bootstrap from './bootstrap/index';\nimport Pending from 'core/pending';\nimport Scroll from './scroll';\nimport setupBootstrapPendingChecks from './pending';\n\n/**\n * Rember the last visited tabs.\n */\nconst rememberTabs = () => {\n    $('a[data-toggle=\"tab\"]').on('shown.bs.tab', function(e) {\n        var hash = $(e.target).attr('href');\n        if (history.replaceState) {\n            history.replaceState(null, null, hash);\n        } else {\n            location.hash = hash;\n        }\n    });\n    const hash = window.location.hash;\n    if (hash) {\n        const tab = document.querySelector('.nav-link[href=\"' + hash + '\"]');\n        if (tab) {\n            tab.click();\n        }\n    }\n};\n\n/**\n * Enable all popovers\n *\n */\nconst enablePopovers = () => {\n    $('body').popover({\n        container: 'body',\n        selector: '[data-toggle=\"popover\"]',\n        trigger: 'focus',\n    });\n\n    document.addEventListener('keydown', e => {\n        if (e.key === 'Escape' && e.target.closest('[data-toggle=\"popover\"]')) {\n            $(e.target).popover('hide');\n        }\n    });\n};\n\n/**\n * Enable tooltips\n *\n */\nconst enableTooltips = () => {\n    $('body').tooltip({\n        container: 'body',\n        selector: '[data-toggle=\"tooltip\"]',\n    });\n};\n\nconst pendingPromise = new Pending('theme_boost/loader:init');\n\n// Add pending promise event listeners to relevant Bootstrap custom events.\nsetupBootstrapPendingChecks();\n\n// Setup Aria helpers for Bootstrap features.\nAria.init();\n\n// Remember the last visited tabs.\nrememberTabs();\n\n// Enable all popovers.\nenablePopovers();\n\n// Enable all tooltips.\nenableTooltips();\n\n// Add scroll handling.\n(new Scroll()).init();\n\n// Disables flipping the dropdowns up and getting hidden behind the navbar.\n$.fn.dropdown.Constructor.Default.flip = false;\n\npendingPromise.resolve();\n\nexport {\n    Bootstrap,\n};\n"],"file":"loader.min.js"}
\ No newline at end of file
diff --git a/theme/boost/amd/src/aria.js b/theme/boost/amd/src/aria.js
index 812aad76680..de4049ebb86 100644
--- a/theme/boost/amd/src/aria.js
+++ b/theme/boost/amd/src/aria.js
@@ -21,7 +21,7 @@
  * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
 
-import {end, escape, arrowUp, arrowDown, home, enter, space} from 'core/key_codes';
+import {end, escape, arrowUp, arrowDown, arrowLeft, arrowRight, home, enter, space} from 'core/key_codes';
 import $ from 'jquery';
 import Pending from 'core/pending';
 
@@ -206,7 +206,87 @@ const autoFocus = () => {
     });
 };
 
+/**
+ * Changes the focus to the correct tab based on the key that is pressed.
+ * @param {KeyboardEvent} e
+ */
+const updateTabFocus = e => {
+    const tabList = e.target.closest('[role="tablist"]');
+    const vertical = tabList.getAttribute('aria-orientation') == 'vertical';
+    const rtl = window.right_to_left();
+    const arrowNext = vertical ? arrowDown : (rtl ? arrowLeft : arrowRight);
+    const arrowPrevious = vertical ? arrowUp : (rtl ? arrowRight : arrowLeft);
+    const tabs = Array.prototype.filter.call(
+        tabList.querySelectorAll('[role="tab"]'),
+        tab => getComputedStyle(tab).display !== 'none'); // We only work with the visible tabs.
+
+    for (let i = 0; i < tabs.length; i++) {
+        tabs[i].index = i;
+    }
+
+    switch (e.keyCode) {
+        case arrowNext:
+            e.preventDefault();
+            if (e.target.index !== undefined && tabs[e.target.index + 1]) {
+                tabs[e.target.index + 1].focus();
+            } else {
+                tabs[0].focus();
+            }
+            break;
+        case arrowPrevious:
+            e.preventDefault();
+            if (e.target.index !== undefined && tabs[e.target.index - 1]) {
+                tabs[e.target.index - 1].focus();
+            } else {
+                tabs[tabs.length - 1].focus();
+            }
+            break;
+        case home:
+            e.preventDefault();
+            tabs[0].focus();
+            break;
+        case end:
+            e.preventDefault();
+            tabs[tabs.length - 1].focus();
+            break;
+        case enter:
+        case space:
+            e.preventDefault();
+            $(e.target).tab('show');
+            tabs.forEach(tab => {
+                tab.tabIndex = -1;
+            });
+            e.target.tabIndex = 0;
+    }
+};
+
+/**
+ * Fix accessibility issues regarding tab elements focus and their tab order in Bootstrap navs.
+ */
+const tabElementFix = () => {
+    document.addEventListener('keydown', e => {
+        if ([arrowUp, arrowDown, arrowLeft, arrowRight, home, end, enter, space].includes(e.keyCode)) {
+            if (e.target.matches('[role="tablist"] [role="tab"]')) {
+                updateTabFocus(e);
+            }
+        }
+    });
+
+    document.addEventListener('click', e => {
+        if (e.target.matches('[role="tablist"] [role="tab"]')) {
+            const tabs = e.target.closest('[role="tablist"]').querySelectorAll('[role="tab"]');
+            e.preventDefault();
+            $(e.target).tab('show');
+            tabs.forEach(tab => {
+                tab.tabIndex = -1;
+            });
+            e.target.tabIndex = 0;
+        }
+    });
+};
+
 export const init = () => {
     dropdownFix();
     autoFocus();
+    tabElementFix();
 };
diff --git a/theme/boost/amd/src/loader.js b/theme/boost/amd/src/loader.js
index c5b8ea582b7..f92a379731c 100644
--- a/theme/boost/amd/src/loader.js
+++ b/theme/boost/amd/src/loader.js
@@ -43,9 +43,12 @@ const rememberTabs = () => {
             location.hash = hash;
         }
     });
-    var hash = window.location.hash;
+    const hash = window.location.hash;
     if (hash) {
-       $('.nav-link[href="' + hash + '"]').tab('show');
+        const tab = document.querySelector('.nav-link[href="' + hash + '"]');
+        if (tab) {
+            tab.click();
+        }
     }
 };
 
@@ -83,6 +86,9 @@ const pendingPromise = new Pending('theme_boost/loader:init');
 // Add pending promise event listeners to relevant Bootstrap custom events.
 setupBootstrapPendingChecks();
 
+// Setup Aria helpers for Bootstrap features.
+Aria.init();
+
 // Remember the last visited tabs.
 rememberTabs();
 
@@ -98,9 +104,6 @@ enableTooltips();
 // Disables flipping the dropdowns up and getting hidden behind the navbar.
 $.fn.dropdown.Constructor.Default.flip = false;
 
-// Setup Aria helpers for Bootstrap features.
-Aria.init();
-
 pendingPromise.resolve();
 
 export {
diff --git a/theme/boost/templates/admin_setting_tabs.mustache b/theme/boost/templates/admin_setting_tabs.mustache
index ec25e9fd81c..162314a4ad9 100644
--- a/theme/boost/templates/admin_setting_tabs.mustache
+++ b/theme/boost/templates/admin_setting_tabs.mustache
@@ -39,7 +39,9 @@
 <ul class="nav nav-tabs" role="tablist">
     {{#tabs}}
         <li class="nav-item">
-            <a href="#{{name}}" class="nav-link {{#active}}active{{/active}}" data-toggle="tab" role="tab">{{displayname}}</a>
+            <a href="#{{name}}" class="nav-link {{#active}}active{{/active}}" data-toggle="tab" role="tab"
+                {{#active}}aria-selected="true"{{/active}}
+                {{^active}}aria-selected="false" tabindex="-1"{{/active}}>{{displayname}}</a>
         </li>
     {{/tabs}}
 </ul>