Regression in e65524382, where what should have been essentially
(window_width / text_width) became (window_width + 1/text_width)
which is not the same at all! What the code was trying to do is
((window_width + 1) / text_width)
Most easily visible in VSE template because it defaults to
MM:SS+FRAME display format, but could be seen in other
animation related windows.
Pull Request: https://projects.blender.org/blender/blender/pulls/147198