diff --git a/phpBB/adm/style/acp_ext_delete_data.html b/phpBB/adm/style/acp_ext_delete_data.html
index 0f3adb7cfe..a07b723e90 100644
--- a/phpBB/adm/style/acp_ext_delete_data.html
+++ b/phpBB/adm/style/acp_ext_delete_data.html
@@ -1,40 +1,40 @@
-<!-- INCLUDE overall_header.html -->
+{% INCLUDE 'overall_header.html' %}
 
 	<a id="maincontent"></a>
 
-	<h1>{L_EXTENSIONS_ADMIN}</h1>
+	<h1>{{ lang('EXTENSIONS_ADMIN') }}</h1>
 
-	<p>{L_EXTENSIONS_EXPLAIN}</p>
-	<p>{L_EXTENSION_DELETE_DATA_EXPLAIN}</p>
+	<p>{{ lang('EXTENSIONS_EXPLAIN') }}</p>
+	<p>{{ lang('EXTENSION_DELETE_DATA_EXPLAIN') }}</p>
 
-	<!-- IF MIGRATOR_ERROR -->
+	{% if MIGRATOR_ERROR %}
 	<div class="errorbox">
-		<p><strong>{L_MIGRATION_EXCEPTION_ERROR}</strong></p>
-		<p>{MIGRATOR_ERROR}</p>
-		<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
+		<p><strong>{{ lang('MIGRATION_EXCEPTION_ERROR') }}</strong></p>
+		<p>{{ MIGRATOR_ERROR }}</p>
+		<p><a href="{{ U_RETURN }}">{{ lang('RETURN_TO_EXTENSION_LIST') }}</a></p>
 	</div>
-	<!-- ELSEIF PRE -->
+	{% elseif PRE %}
 	<div class="errorbox">
-		<p>{L_CONFIRM_MESSAGE}</p>
+		<p>{{ lang('CONFIRM_MESSAGE') }}</p>
 	</div>
 
-	<form id="acp_extensions" method="post" action="{U_PURGE}">
+	<form id="acp_extensions" method="post" action="{{ U_PURGE }}">
 	<fieldset class="submit-buttons">
-		<legend>{L_EXTENSION_DELETE_DATA}</legend>
-		<input class="button1" type="submit" name="delete_data" value="{L_EXTENSION_DELETE_DATA}" />
-		<input class="button2" type="submit" name="cancel" value="{L_CANCEL}" />
+		<legend>{{ lang('EXTENSION_DELETE_DATA') }}</legend>
+		<input class="button1" type="submit" name="delete_data" value="{{ lang('EXTENSION_DELETE_DATA') }}" />
+		<input class="button2" type="submit" name="cancel" value="{{ lang('CANCEL') }}" />
 	</fieldset>
 	</form>
-	<!-- ELSEIF S_NEXT_STEP -->
+	{% elseif S_NEXT_STEP %}
 		<div class="errorbox">
-			<p>{L_EXTENSION_DELETE_DATA_IN_PROGRESS}</p>
+			<p>{{ lang('EXTENSION_DELETE_DATA_IN_PROGRESS') }}</p>
 		</div>
-	<!-- ELSE -->
+	{% else %}
 		<div class="successbox">
-			<p>{L_EXTENSION_DELETE_DATA_SUCCESS}</p>
+			<p>{{ lang('EXTENSION_DELETE_DATA_SUCCESS') }}</p>
 			<br />
-			<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
+			<p><a href="{{ U_RETURN }}">{{ lang('RETURN_TO_EXTENSION_LIST') }}</a></p>
 		</div>
-	<!-- ENDIF -->
+	{% endif %}
 
-<!-- INCLUDE overall_footer.html -->
+{% INCLUDE 'overall_footer.html' %}
diff --git a/phpBB/adm/style/acp_ext_disable.html b/phpBB/adm/style/acp_ext_disable.html
index d2b5c46fe8..3285b7f46d 100644
--- a/phpBB/adm/style/acp_ext_disable.html
+++ b/phpBB/adm/style/acp_ext_disable.html
@@ -1,34 +1,34 @@
-<!-- INCLUDE overall_header.html -->
+{% INCLUDE 'overall_header.html' %}
 
 	<a id="maincontent"></a>
 
-	<h1>{L_EXTENSIONS_ADMIN}</h1>
+	<h1>{{ lang('EXTENSIONS_ADMIN') }}</h1>
 
-	<p>{L_EXTENSIONS_EXPLAIN}</p>
-	<p>{L_EXTENSION_DISABLE_EXPLAIN}</p>
+	<p>{{ lang('EXTENSIONS_EXPLAIN') }}</p>
+	<p>{{ lang('EXTENSION_DISABLE_EXPLAIN') }}</p>
 
-	<!-- IF PRE -->
+	{% if PRE %}
 	<fieldset>
-		<h2>{L_CONFIRM}</h2>
-		<p>{L_CONFIRM_MESSAGE}</p>
+		<h2>{{ lang('CONFIRM') }}</h2>
+		<p>{{ lang('CONFIRM_MESSAGE') }}</p>
 	</fieldset>
 
-	<form id="acp_extensions" method="post" action="{U_DISABLE}">
+	<form id="acp_extensions" method="post" action="{{ U_DISABLE }}">
 	<fieldset class="submit-buttons">
-		<input class="button1" type="submit" name="disable" value="{L_EXTENSION_DISABLE}" />
-		<input class="button2" type="submit" name="cancel" value="{L_CANCEL}" />
+		<input class="button1" type="submit" name="disable" value="{{ lang('EXTENSION_DISABLE') }}" />
+		<input class="button2" type="submit" name="cancel" value="{{ lang('CANCEL') }}" />
 	</fieldset>
 	</form>
-	<!-- ELSEIF S_NEXT_STEP -->
+	{% elseif S_NEXT_STEP %}
 		<div class="successbox notice">
-			<p>{L_EXTENSION_DISABLE_IN_PROGRESS}</p>
+			<p>{{ lang('EXTENSION_DISABLE_IN_PROGRESS') }}</p>
 		</div>
-	<!-- ELSE -->
+	{% else %}
 		<div class="successbox">
-			<p>{L_EXTENSION_DISABLE_SUCCESS}</p>
+			<p>{{ lang('EXTENSION_DISABLE_SUCCESS') }}</p>
 			<br />
-			<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
+			<p><a href="{{ U_RETURN }}">{{ lang('RETURN_TO_EXTENSION_LIST') }}</a></p>
 		</div>
-	<!-- ENDIF -->
+	{% endif %}
 
-<!-- INCLUDE overall_footer.html -->
+{% INCLUDE 'overall_footer.html' %}
diff --git a/phpBB/adm/style/acp_ext_enable.html b/phpBB/adm/style/acp_ext_enable.html
index 8a4a35359e..ab6b2aa046 100644
--- a/phpBB/adm/style/acp_ext_enable.html
+++ b/phpBB/adm/style/acp_ext_enable.html
@@ -1,40 +1,40 @@
-<!-- INCLUDE overall_header.html -->
+{% INCLUDE 'overall_header.html' %}
 
 	<a id="maincontent"></a>
 
-	<h1>{L_EXTENSIONS_ADMIN}</h1>
+	<h1>{{ lang('EXTENSIONS_ADMIN') }}</h1>
 
-	<p>{L_EXTENSIONS_EXPLAIN}</p>
-	<p>{L_EXTENSION_ENABLE_EXPLAIN}</p>
+	<p>{{ lang('EXTENSIONS_EXPLAIN') }}</p>
+	<p>{{ lang('EXTENSION_ENABLE_EXPLAIN') }}</p>
 
-	<!-- IF MIGRATOR_ERROR -->
+	{% if MIGRATOR_ERROR %}
 	<div class="errorbox">
-		<p><strong>{L_MIGRATION_EXCEPTION_ERROR}</strong></p>
-		<p>{MIGRATOR_ERROR}</p>
-		<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
+		<p><strong>{{ lang('MIGRATION_EXCEPTION_ERROR') }}</strong></p>
+		<p>{{ MIGRATOR_ERROR }}</p>
+		<p><a href="{{ U_RETURN }}">{{ lang('RETURN_TO_EXTENSION_LIST') }}</a></p>
 	</div>
-	<!-- ELSEIF PRE -->
+	{% elseif PRE %}
 	<fieldset>
-		<h2>{L_CONFIRM}</h2>
-		<p>{L_CONFIRM_MESSAGE}</p>
+		<h2>{{ lang('CONFIRM') }}</h2>
+		<p>{{ lang('CONFIRM_MESSAGE') }}</p>
 	</fieldset>
 
-	<form id="acp_extensions" method="post" action="{U_ENABLE}">
+	<form id="acp_extensions" method="post" action="{{ U_ENABLE }}">
 	<fieldset class="submit-buttons">
-		<input class="button1" type="submit" name="enable" value="{L_EXTENSION_ENABLE}" />
-		<input class="button2" type="submit" name="cancel" value="{L_CANCEL}" />
+		<input class="button1" type="submit" name="enable" value="{{ lang('EXTENSION_ENABLE') }}" />
+		<input class="button2" type="submit" name="cancel" value="{{ lang('CANCEL') }}" />
 	</fieldset>
 	</form>
-	<!-- ELSEIF S_NEXT_STEP -->
+	{% elseif S_NEXT_STEP %}
 		<div class="successbox notice">
-			<p>{L_EXTENSION_ENABLE_IN_PROGRESS}</p>
+			<p>{{ lang('EXTENSION_ENABLE_IN_PROGRESS') }}</p>
 		</div>
-	<!-- ELSE -->
+	{% else %}
 		<div class="successbox">
-			<p>{L_EXTENSION_ENABLE_SUCCESS}</p>
+			<p>{{ lang('EXTENSION_ENABLE_SUCCESS') }}</p>
 			<br />
-			<p><a href="{U_RETURN}">{L_RETURN_TO_EXTENSION_LIST}</a></p>
+			<p><a href="{{ U_RETURN }}">{{ lang('RETURN_TO_EXTENSION_LIST') }}</a></p>
 		</div>
-	<!-- ENDIF -->
+	{% endif %}
 
-<!-- INCLUDE overall_footer.html -->
+{% INCLUDE 'overall_footer.html' %}