BUG: Filtering by tag in mobile app

The filter doesn't work if a tag is part of another tag.

Example:

In the desktop app, I tag one resource with "a", another resource with "ab", and a third resource with "abc".

I go to the mobile app (latest version from Google Play), wait for the library to sync, and can now apply the filter according to the three new tags.

If I filter for the tag "a", all three resources show up (with tags "a", "ab" and "abc"). If I filter for the tag "ab", two resources show up (with tags "ab" and "abc"). If I filter for "abc", the filter works correctly, and only one resource showa up.