Created attachment 115032 [details]
See the scroll bar of 'wchar.h' document

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OS: Fedora 27 or 28 x86_64
Desktop Environment: MATE 1.20.3
Window Manager: Compiz 0.8.14
File Manager: Caja 1.20.2
Kate: 17.12.2 (fedora 27)
      18.04.3 (fedora 28)
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When I open multiple files via context menu (right click on multiple files in file manager, then click open with Kate), then sometimes (not always) one or more document views will not expand it's colorful scroll bar to max height.

See the screen record in the attachment: see the 'wchar.h' one.


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How to reproduce:
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It's not always reproducible, but in most cases, the following will help to reproduce this issue:
* Kate editor must been opened first
* Windows of Kate editor should be maximized

Then, select multiple files in file manager --> right click on these selected files --> Open with Kate.



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When this happened:
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* a simple window resize operation will make the scroll bar expand to max height.
* it never happened on the first (i mean the left most) document.