Bug 449865

Summary: Trim margins: irregular behavior which hinders page-by-page navigation
Product: [Applications] okular Reporter: rgreen <greenandpleasant2000-support>
Component: generalAssignee: Okular developers <okular-devel>
Status: REPORTED ---    
Severity: normal    
Priority: NOR    
Version First Reported In: unspecified   
Target Milestone: ---   
Platform: Mint (Ubuntu based)   
OS: Linux   
Latest Commit: Version Fixed In:
Sentry Crash Report:
Attachments: PDF doc. showing navigation issue with "Trim Margins"

Description rgreen 2022-02-09 14:52:43 UTC 
Created attachment 146493 [details]
PDF doc. showing navigation issue with "Trim Margins"

SUMMARY
***
(Originally filed at Bug 449492).

When you trim margins you should be able to reduce the width of the program window to just encompass the trimmed document width, AND still be able to navigate page-by-page using the keyboard L/R arrows. However there is a bug somewhere that prevents this happening under MOST (but not all) circumstances, and the document is behaving, for navigation purposes, as if the marins are still present.
***
After some investigation I was able to come up with a formula to successfully minimize the width of the program window without interfering with page-by-page keyboard arrow navigation:

1. Open the attached pdf document and set to page 1.
2. Trim margins and reduce the width of the window slightly, so that a scroll bar appears (even though it shouldn't since there should still be plenty of space around the trimmed sides.
3. Close the pdf doc. and reopen.
4. Now use the mouse wheel to scroll down through the pages.

RESULT: The horizontal scroll bar disappears at page 9! Now the document width can be reduced to the trim margins.

5. Close and reopen the program.

RESULT: The horizontal scroll bar appears again! 

SOFTWARE/OS VERSIONS

Linux/KDE Plasma: Linux Mint 20.
KDE Plasma Version: 
KDE Frameworks Version: 5.89.0
Qt Version: 5.15.3