diff --git a/lib/classes/output/progress_trace.php b/lib/classes/output/progress_trace.php
new file mode 100644
index 00000000000..8259ddb7d71
--- /dev/null
+++ b/lib/classes/output/progress_trace.php
@@ -0,0 +1,41 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Progress trace class.
+ *
+ * Use this class from long operations where you want to output occasional information about
+ * what is going on, but don't know if, or in what format, the output should be.
+ *
+ * @copyright 2009 Tim Hunt
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+abstract class progress_trace {
+    /**
+     * Output an progress message in whatever format.
+     *
+     * @param string $message the message to output.
+     * @param integer $depth indent depth for this message.
+     */
+    abstract public function output($message, $depth = 0);
+
+    /**
+     * Called when the processing is finished.
+     */
+    public function finished() {
+    }
+}
diff --git a/lib/classes/output/progress_trace/combined_progress_trace.php b/lib/classes/output/progress_trace/combined_progress_trace.php
new file mode 100644
index 00000000000..084114de521
--- /dev/null
+++ b/lib/classes/output/progress_trace/combined_progress_trace.php
@@ -0,0 +1,61 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Special type of trace that can be used for redirecting to multiple other traces.
+ *
+ * @copyright Petr Skoda {@link http://skodak.org}
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class combined_progress_trace extends progress_trace {
+
+    /**
+     * An array of traces.
+     * @var array
+     */
+    protected $traces;
+
+    /**
+     * Constructs a new instance.
+     *
+     * @param array $traces multiple traces
+     */
+    public function __construct(array $traces) {
+        $this->traces = $traces;
+    }
+
+    /**
+     * Output an progress message in whatever format.
+     *
+     * @param string $message the message to output.
+     * @param integer $depth indent depth for this message.
+     */
+    public function output($message, $depth = 0) {
+        foreach ($this->traces as $trace) {
+            $trace->output($message, $depth);
+        }
+    }
+
+    /**
+     * Called when the processing is finished.
+     */
+    public function finished() {
+        foreach ($this->traces as $trace) {
+            $trace->finished();
+        }
+    }
+}
diff --git a/lib/classes/output/progress_trace/error_log_progress_trace.php b/lib/classes/output/progress_trace/error_log_progress_trace.php
new file mode 100644
index 00000000000..f27d5e791a1
--- /dev/null
+++ b/lib/classes/output/progress_trace/error_log_progress_trace.php
@@ -0,0 +1,46 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This subclass of progress_trace outputs to error log.
+ *
+ * @copyright Petr Skoda {@link http://skodak.org}
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class error_log_progress_trace extends progress_trace {
+    /** @var string log prefix */
+    protected $prefix;
+
+    /**
+     * Constructor.
+     * @param string $prefix optional log prefix
+     */
+    public function __construct($prefix = '') {
+        $this->prefix = $prefix;
+    }
+
+    /**
+     * Output the trace message.
+     *
+     * @param string $message
+     * @param int $depth
+     * @return void Output is sent to error log.
+     */
+    public function output($message, $depth = 0) {
+        error_log($this->prefix . str_repeat('  ', $depth) . $message);
+    }
+}
diff --git a/lib/classes/output/progress_trace/html_list_progress_trace.php b/lib/classes/output/progress_trace/html_list_progress_trace.php
new file mode 100644
index 00000000000..ef1629fb04b
--- /dev/null
+++ b/lib/classes/output/progress_trace/html_list_progress_trace.php
@@ -0,0 +1,66 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * HTML List Progress Tree
+ *
+ * @copyright 2009 Tim Hunt
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class html_list_progress_trace extends progress_trace {
+    /** @var int */
+    protected $currentdepth = -1;
+
+    /**
+     * Echo out the list
+     *
+     * @param string $message The message to display
+     * @param int $depth
+     * @return void Output is echoed
+     */
+    public function output($message, $depth = 0) {
+        $samedepth = true;
+        while ($this->currentdepth > $depth) {
+            echo "</li>\n</ul>\n";
+            $this->currentdepth -= 1;
+            if ($this->currentdepth == $depth) {
+                echo '<li>';
+            }
+            $samedepth = false;
+        }
+        while ($this->currentdepth < $depth) {
+            echo "<ul>\n<li>";
+            $this->currentdepth += 1;
+            $samedepth = false;
+        }
+        if ($samedepth) {
+            echo "</li>\n<li>";
+        }
+        echo htmlspecialchars($message, ENT_COMPAT);
+        flush();
+    }
+
+    /**
+     * Called when the processing is finished.
+     */
+    public function finished() {
+        while ($this->currentdepth >= 0) {
+            echo "</li>\n</ul>\n";
+            $this->currentdepth -= 1;
+        }
+    }
+}
diff --git a/lib/classes/output/progress_trace/html_progress_trace.php b/lib/classes/output/progress_trace/html_progress_trace.php
new file mode 100644
index 00000000000..93208f62c78
--- /dev/null
+++ b/lib/classes/output/progress_trace/html_progress_trace.php
@@ -0,0 +1,36 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This subclass of progress_trace outputs as HTML.
+ *
+ * @copyright 2009 Tim Hunt
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class html_progress_trace extends progress_trace {
+    /**
+     * Output the trace message.
+     *
+     * @param string $message
+     * @param int $depth
+     * @return void Output is echo'd
+     */
+    public function output($message, $depth = 0) {
+        echo '<p>', str_repeat('&#160;&#160;', $depth), htmlspecialchars($message, ENT_COMPAT), "</p>\n";
+        flush();
+    }
+}
diff --git a/lib/classes/output/progress_trace/null_progress_trace.php b/lib/classes/output/progress_trace/null_progress_trace.php
new file mode 100644
index 00000000000..c0b1def2680
--- /dev/null
+++ b/lib/classes/output/progress_trace/null_progress_trace.php
@@ -0,0 +1,34 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This subclass of progress_trace does not ouput anything.
+ *
+ * @copyright 2009 Tim Hunt
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class null_progress_trace extends progress_trace {
+    /**
+     * Does Nothing
+     *
+     * @param string $message
+     * @param int $depth
+     * @return void Does Nothing
+     */
+    public function output($message, $depth = 0) {
+    }
+}
diff --git a/lib/classes/output/progress_trace/progress_trace_buffer.php b/lib/classes/output/progress_trace/progress_trace_buffer.php
new file mode 100644
index 00000000000..68788c46721
--- /dev/null
+++ b/lib/classes/output/progress_trace/progress_trace_buffer.php
@@ -0,0 +1,90 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Special type of trace that can be used for catching of output of other traces.
+ *
+ * @copyright Petr Skoda {@link http://skodak.org}
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class progress_trace_buffer extends progress_trace {
+    /** @var progress_trace */
+    protected $trace;
+    /** @var bool do we pass output out */
+    protected $passthrough;
+    /** @var string output buffer */
+    protected $buffer;
+
+    /**
+     * Constructor.
+     *
+     * @param progress_trace $trace
+     * @param bool $passthrough true means output and buffer, false means just buffer and no output
+     */
+    public function __construct(progress_trace $trace, $passthrough = true) {
+        $this->trace       = $trace;
+        $this->passthrough = $passthrough;
+        $this->buffer      = '';
+    }
+
+    /**
+     * Output the trace message.
+     *
+     * @param string $message the message to output.
+     * @param int $depth indent depth for this message.
+     * @return void output stored in buffer
+     */
+    public function output($message, $depth = 0) {
+        ob_start();
+        $this->trace->output($message, $depth);
+        $this->buffer .= ob_get_contents();
+        if ($this->passthrough) {
+            ob_end_flush();
+        } else {
+            ob_end_clean();
+        }
+    }
+
+    /**
+     * Called when the processing is finished.
+     */
+    public function finished() {
+        ob_start();
+        $this->trace->finished();
+        $this->buffer .= ob_get_contents();
+        if ($this->passthrough) {
+            ob_end_flush();
+        } else {
+            ob_end_clean();
+        }
+    }
+
+    /**
+     * Reset internal text buffer.
+     */
+    public function reset_buffer() {
+        $this->buffer = '';
+    }
+
+    /**
+     * Return internal text buffer.
+     * @return string buffered plain text
+     */
+    public function get_buffer() {
+        return $this->buffer;
+    }
+}
diff --git a/lib/classes/output/progress_trace/text_progress_trace.php b/lib/classes/output/progress_trace/text_progress_trace.php
new file mode 100644
index 00000000000..21ee17f449b
--- /dev/null
+++ b/lib/classes/output/progress_trace/text_progress_trace.php
@@ -0,0 +1,35 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * This subclass of progress_trace outputs to plain text.
+ *
+ * @copyright 2009 Tim Hunt
+ * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ * @package core
+ */
+class text_progress_trace extends progress_trace {
+    /**
+     * Output the trace message.
+     *
+     * @param string $message
+     * @param int $depth
+     * @return void Output is echo'd
+     */
+    public function output($message, $depth = 0) {
+        mtrace(str_repeat('  ', $depth) . $message);
+    }
+}
diff --git a/lib/db/legacyclasses.php b/lib/db/legacyclasses.php
index 0cc09322714..bc77cabdbd6 100644
--- a/lib/db/legacyclasses.php
+++ b/lib/db/legacyclasses.php
@@ -43,4 +43,14 @@ $legacyclasses = [
     \require_login_session_timeout_exception::class => 'exception/require_login_session_timeout_exception.php',
     \required_capability_exception::class => 'exception/required_capability_exception.php',
     \webservice_parameter_exception::class => 'exception/webservice_parameter_exception.php',
+
+    // The progress_trace classes.
+    \combined_progress_trace::class => 'output/progress_trace/combined_progress_trace.php',
+    \error_log_progress_trace::class => 'output/progress_trace/error_log_progress_trace.php',
+    \html_list_progress_trace::class => 'output/progress_trace/html_list_progress_trace.php',
+    \html_progress_trace::class => 'output/progress_trace/html_progress_trace.php',
+    \null_progress_trace::class => 'output/progress_trace/null_progress_trace.php',
+    \progress_trace::class => 'output/progress_trace.php',
+    \progress_trace_buffer::class => 'output/progress_trace/progress_trace_buffer.php',
+    \text_progress_trace::class => 'output/progress_trace/text_progress_trace.php',
 ];
diff --git a/lib/weblib.php b/lib/weblib.php
index 7e9634c890c..e1a0bd345af 100644
--- a/lib/weblib.php
+++ b/lib/weblib.php
@@ -79,9 +79,6 @@ define('URL_MATCH_PARAMS', 1);
  */
 define('URL_MATCH_EXACT', 2);
 
-// TODO MDL-81933 Remove after Moodle 4.5 release.
-require_once($CFG->libdir . '/classes/url.php');
-
 // Functions.
 
 /**
@@ -2591,295 +2588,6 @@ function is_in_popup() {
     return ($inpopup);
 }
 
-/**
- * Progress trace class.
- *
- * Use this class from long operations where you want to output occasional information about
- * what is going on, but don't know if, or in what format, the output should be.
- *
- * @copyright 2009 Tim Hunt
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-abstract class progress_trace {
-    /**
-     * Output an progress message in whatever format.
-     *
-     * @param string $message the message to output.
-     * @param integer $depth indent depth for this message.
-     */
-    abstract public function output($message, $depth = 0);
-
-    /**
-     * Called when the processing is finished.
-     */
-    public function finished() {
-    }
-}
-
-/**
- * This subclass of progress_trace does not ouput anything.
- *
- * @copyright 2009 Tim Hunt
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class null_progress_trace extends progress_trace {
-    /**
-     * Does Nothing
-     *
-     * @param string $message
-     * @param int $depth
-     * @return void Does Nothing
-     */
-    public function output($message, $depth = 0) {
-    }
-}
-
-/**
- * This subclass of progress_trace outputs to plain text.
- *
- * @copyright 2009 Tim Hunt
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class text_progress_trace extends progress_trace {
-    /**
-     * Output the trace message.
-     *
-     * @param string $message
-     * @param int $depth
-     * @return void Output is echo'd
-     */
-    public function output($message, $depth = 0) {
-        mtrace(str_repeat('  ', $depth) . $message);
-    }
-}
-
-/**
- * This subclass of progress_trace outputs as HTML.
- *
- * @copyright 2009 Tim Hunt
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class html_progress_trace extends progress_trace {
-    /**
-     * Output the trace message.
-     *
-     * @param string $message
-     * @param int $depth
-     * @return void Output is echo'd
-     */
-    public function output($message, $depth = 0) {
-        echo '<p>', str_repeat('&#160;&#160;', $depth), htmlspecialchars($message, ENT_COMPAT), "</p>\n";
-        flush();
-    }
-}
-
-/**
- * HTML List Progress Tree
- *
- * @copyright 2009 Tim Hunt
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class html_list_progress_trace extends progress_trace {
-    /** @var int */
-    protected $currentdepth = -1;
-
-    /**
-     * Echo out the list
-     *
-     * @param string $message The message to display
-     * @param int $depth
-     * @return void Output is echoed
-     */
-    public function output($message, $depth = 0) {
-        $samedepth = true;
-        while ($this->currentdepth > $depth) {
-            echo "</li>\n</ul>\n";
-            $this->currentdepth -= 1;
-            if ($this->currentdepth == $depth) {
-                echo '<li>';
-            }
-            $samedepth = false;
-        }
-        while ($this->currentdepth < $depth) {
-            echo "<ul>\n<li>";
-            $this->currentdepth += 1;
-            $samedepth = false;
-        }
-        if ($samedepth) {
-            echo "</li>\n<li>";
-        }
-        echo htmlspecialchars($message, ENT_COMPAT);
-        flush();
-    }
-
-    /**
-     * Called when the processing is finished.
-     */
-    public function finished() {
-        while ($this->currentdepth >= 0) {
-            echo "</li>\n</ul>\n";
-            $this->currentdepth -= 1;
-        }
-    }
-}
-
-/**
- * This subclass of progress_trace outputs to error log.
- *
- * @copyright Petr Skoda {@link http://skodak.org}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class error_log_progress_trace extends progress_trace {
-    /** @var string log prefix */
-    protected $prefix;
-
-    /**
-     * Constructor.
-     * @param string $prefix optional log prefix
-     */
-    public function __construct($prefix = '') {
-        $this->prefix = $prefix;
-    }
-
-    /**
-     * Output the trace message.
-     *
-     * @param string $message
-     * @param int $depth
-     * @return void Output is sent to error log.
-     */
-    public function output($message, $depth = 0) {
-        error_log($this->prefix . str_repeat('  ', $depth) . $message);
-    }
-}
-
-/**
- * Special type of trace that can be used for catching of output of other traces.
- *
- * @copyright Petr Skoda {@link http://skodak.org}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class progress_trace_buffer extends progress_trace {
-    /** @var progress_trace */
-    protected $trace;
-    /** @var bool do we pass output out */
-    protected $passthrough;
-    /** @var string output buffer */
-    protected $buffer;
-
-    /**
-     * Constructor.
-     *
-     * @param progress_trace $trace
-     * @param bool $passthrough true means output and buffer, false means just buffer and no output
-     */
-    public function __construct(progress_trace $trace, $passthrough = true) {
-        $this->trace       = $trace;
-        $this->passthrough = $passthrough;
-        $this->buffer      = '';
-    }
-
-    /**
-     * Output the trace message.
-     *
-     * @param string $message the message to output.
-     * @param int $depth indent depth for this message.
-     * @return void output stored in buffer
-     */
-    public function output($message, $depth = 0) {
-        ob_start();
-        $this->trace->output($message, $depth);
-        $this->buffer .= ob_get_contents();
-        if ($this->passthrough) {
-            ob_end_flush();
-        } else {
-            ob_end_clean();
-        }
-    }
-
-    /**
-     * Called when the processing is finished.
-     */
-    public function finished() {
-        ob_start();
-        $this->trace->finished();
-        $this->buffer .= ob_get_contents();
-        if ($this->passthrough) {
-            ob_end_flush();
-        } else {
-            ob_end_clean();
-        }
-    }
-
-    /**
-     * Reset internal text buffer.
-     */
-    public function reset_buffer() {
-        $this->buffer = '';
-    }
-
-    /**
-     * Return internal text buffer.
-     * @return string buffered plain text
-     */
-    public function get_buffer() {
-        return $this->buffer;
-    }
-}
-
-/**
- * Special type of trace that can be used for redirecting to multiple other traces.
- *
- * @copyright Petr Skoda {@link http://skodak.org}
- * @license http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
- * @package core
- */
-class combined_progress_trace extends progress_trace {
-
-    /**
-     * An array of traces.
-     * @var array
-     */
-    protected $traces;
-
-    /**
-     * Constructs a new instance.
-     *
-     * @param array $traces multiple traces
-     */
-    public function __construct(array $traces) {
-        $this->traces = $traces;
-    }
-
-    /**
-     * Output an progress message in whatever format.
-     *
-     * @param string $message the message to output.
-     * @param integer $depth indent depth for this message.
-     */
-    public function output($message, $depth = 0) {
-        foreach ($this->traces as $trace) {
-            $trace->output($message, $depth);
-        }
-    }
-
-    /**
-     * Called when the processing is finished.
-     */
-    public function finished() {
-        foreach ($this->traces as $trace) {
-            $trace->finished();
-        }
-    }
-}
-
 /**
  * Returns a localized sentence in the current language summarizing the current password policy
  *