I doubt that is the reason. The tag-line will just jump the whole line of text if such a resize takes place. You would not get a black line to hide it -- at least, that is the case in acme on native Plan 9. Where are you using it?
ak
--- Begin Message ---its because you dont want half a line of text shown. it can only resize and have the thin bar for full increments of text. Mog
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