I have this same issue! I use aDHTMLX layout with several “panes” some of which have a toolbar running across the top. When the resizing feature of the layout is exercised, it iis very possible to have parts of the toolbars truncated, as Bystriansky describes. It would be ideal of course if your control automatically responded and created the requisite drop-down list of tabbar options not visible.
For Bystriansky … One technique I employed to deal with this is to have two versions of the tabbar, one for “beginners” and one for “experts.” The former has the text labels with the buttons and the latter does not (thereby reducing the real estate required to present the tabbar options). See below… the custom button at the left (that looks a little like a vertical slider) controls whether or not the text labels are included. In beginner mode I have all tooltips off, but in expert I copy the text to the tooltip.
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