Issue 7048 - Fix erroneous markup escaping in translation strings

cms/converters.py

 # This file is part of the Adblock Plus web scripts,
 # Copyright (C) 2006-present eyeo GmbH
 #
 # Adblock Plus is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License version 3 as
 # published by the Free Software Foundation.
 #
 # Adblock Plus 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
@@ skipping 132 matching lines @@
         # Handle duplicated strings
         if default:
             self._seen_defaults[(page, name)] = (default, comment)
         else:
             try:
                 default, comment = self._seen_defaults[(page, name)]
             except KeyError:
                 raise Exception('Text not yet defined for string {} on page'
                                 ' {}'.format(name, page))
 
+        full_default = default
         # Extract tag attributes from default string
         default, saved_attributes, fixed_strings = (
             self._attribute_parser.parse(default, self._params['page']))
 
         # Get translation
         locale = self._params['locale']
         if locale == self._params['defaultlocale']:
             result = default
         elif name in localedata:
             result = localedata[name].strip()
+            # If the string is present in default locale, but not in the
+            # current one, we will get the value from default locale here.
+            # If it happens to contain attributes on any tags, those need
+            # to be stripped, otherwise the attribute substitution below won't
+            # work. Luckily, we already have the default translation string
+            # with attributes stripped -- it's the value of `default`.
+            if result == full_default.strip():
+                result = default
         else:
             result = default
             self.missing_translations += 1
         self.total_translations += 1
 
         # Perform callback with the string if required, e.g. for the
         # translations script
         callback = self._params['localized_string_callback']
         if callback:
             callback(page, locale, name, result, comment, fixed_strings)
@@ skipping 350 matching lines @@
             stack[-1]['subitems'].append(item)
             stack.append(item)
         return structured
 
 
 converters = {
     'html': RawConverter,
     'md': MarkdownConverter,
     'tmpl': TemplateConverter,
 }