User reports:
One thing is really disturbing:

In micro-pause dialog is string:
_("Next rest break in %s"),
It looks like: Next rest break in 34:56.

Now: when seconds are running width of string constantly changes.
With string also _whole dialog_ is changing its width. Problem may be 
not visible in en_xx locale because string is narrower than progress bar 
but because Polish translation (and possible other localizations) is 
quite long, problem is visible.

Short term solution is to reduce precision. Are in such dialog seconds 
really needed? For the time left yes, for anything other no.

This is common GTK problem. _All_ numbers, dates, etc. are moving, 
moving, moving... It is especially disturbing in workrave when window 
can be almost always visible.

Fixed. Disabled resizing of the micro break window. 

It looks as if other windows don't suffer from this problem...