Hmm thanks, I still can’t explain this logically in any way. There are no issues with it in other widgets which also use filters.
But as soon as I use ANY RegExp-based filter together with the main filter, it breaks.
If I e.g. do:
INCL Title “contains” “word” → works fine
But:
INCL Title “RegExp match” “word” → is ignored (no results)
Update:
But I have found the reason now:
“RegExp Match” is a FULL Match (other than what I would expect, because RegExp matches are usually “contains” matches unless specified otherwise, e.g. in JS “dog”.match(/do/) returns something. This is also how the RegExp “match” works for Google Analytics data. It would imho be good if Piwik followed the same logic or makes this clearer.
So in short, if I use
“RegExp match” “.word.”, it works.