[web/debug] Fix check for open sessions
itervalues returns an iterator, which never evaluates to False.
Regression from 0bb18407c053 "[toward py3k] rewrite dict.keys() and
dict.values() (part of #2711624)".
CSS Coding Standards--------------------(Draft, to be continued):Naming: camelCaseIndentation rules~~~~~~~~~~~~~~~~~- 2 espaces avant les propriétés- pas d'espace avant les ":", un espace après- 1 seul espace entre les différentes valeurs pour une même propriétéDocumentation~~~~~~~~~~~~~Please keep rules semantically linked grouped together, with a comment aboutwhat they are for.Recommendation~~~~~~~~~~~~~~- Try to use existing classes rather than introduce new ones- Keep things as simple as possible while in the framework- Think about later customization by application- Avoid introducing a new CSS file for a few lines of CSS, at least while the framework doesn't include packing functionalities