Bug 407569 - Extra padding in Plasmashell when switching from Xorg to Wayland
Summary: Extra padding in Plasmashell when switching from Xorg to Wayland
Status: RESOLVED FIXED
Alias: None
Product: plasmashell
Classification: Plasma
Component: Theme - Breeze (show other bugs)
Version: 5.15.5
Platform: Neon Linux
: NOR normal
Target Milestone: 1.0
Assignee: visual-design
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2019-05-15 19:46 UTC by Tore Havn
Modified: 2020-09-07 10:47 UTC (History)
2 users (show)

See Also:
Latest Commit:
Version Fixed In:


Attachments
Combined two screenshots of Kicker: the inserted/rightmost is in Xorg, and the leftmost is afterwards in Wayland (230.48 KB, image/png)
2019-05-15 19:46 UTC, Tore Havn
Details
Kicker under Wayland, with a different theme (147.00 KB, image/png)
2019-05-16 18:02 UTC, Tore Havn
Details
Kicker under Xorg, with a different theme (268.58 KB, image/png)
2019-05-16 18:02 UTC, Tore Havn
Details

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Description Tore Havn 2019-05-15 19:46:22 UTC
Created attachment 120088 [details]
Combined two screenshots of Kicker: the inserted/rightmost is in Xorg, and the leftmost is afterwards in Wayland

SUMMARY
Wanting to test out Wayland more, I logged out of Plasma under Xorg and logged in to Plasma under Wayland.

Once there, the padding is much larger than expected.

See the attachment, where I have combined two screenshots of Kicker. The inserted/rightmost is in Xorg, and the leftmost is afterwards in Wayland.

STEPS TO REPRODUCE
1. Having logged in to Plasma under Xorg
2. Logging out and loggin in to Plasma under Wayland

OBSERVED RESULT
The padding in Plasmashell is larger than expected.

EXPECTED RESULT
The padding should have been similar under Wayland as under Xorg.

SOFTWARE/OS VERSIONS
KDE neon User Edition
KDE Plasma Version: 5.15.5
KDE Frameworks Version: 5.58
Qt Version: 5.12.0

ADDITIONAL INFORMATION
I tried to report this earlier with https://bugs.kde.org/show_bug.cgi?id=398636, and David Edmundson found a workaround.

This is still a problem however, and shouldn't happen.
Comment 1 Nate Graham 2019-05-15 20:08:12 UTC
Does this happen with only the Breeze Plasma theme, or other Plasma themes as well?
Comment 2 Tore Havn 2019-05-16 18:01:18 UTC
I have never tried to play around much with themes, but while using Wayland I went and downloaded the «Honeycrisp KDE» (called «OSX Absurdity» when installed) theme.

After applying it I took a screenshot again, logged out and logged in using Xorg, and took a new screenshot. I've uploaded the two images here. (The difference in icons could be because I also switched to regular Breeze inbetween.)

While it is not uniform, it does look like in general, the Xorg versions have less padding than the Wayland versions.
Comment 3 Tore Havn 2019-05-16 18:02:14 UTC
Created attachment 120113 [details]
Kicker under Wayland, with a different theme
Comment 4 Tore Havn 2019-05-16 18:02:34 UTC
Created attachment 120114 [details]
Kicker under Xorg, with a different theme
Comment 5 Tore Havn 2019-05-16 18:03:38 UTC
However, after looking more on this, I suspect that the root cause here is a difference in how the display scaling works between Xorg and Wayland.

I forgot to include this in the first post, but I have a 13" laptop with 4K display, so I run Plasma with 2x scaling.

Looking at the last two screenshots, it should be obvious that their scale is different (which I can't explain). However, notice how it seems that the horizontal padding around the Favourite icons seems to be attempting being the same real size in the two screenshots, while the vertical padding is larger under Xorg.
Comment 6 Christoph Feck 2019-05-30 18:16:57 UTC
New information was added; changing status for inspection.
Comment 7 Nate Graham 2020-07-24 18:23:38 UTC
What I suspect is going on here is that you're experiencing the difference between the Wayland session using Qt scaling, and the X11 session not using Qt scaling and instead running at an effective scale of 1X but with larger fonts and UI elements scaled up accordingly. This generally causes paddings and margins to not scale up as much. So you are probably seeing things on Wayland the way they were meant to be see, given that Qt scaling is in use.

If you're still experiencing this with Plasma 5.19 (or better yet, git master), can you set PLASMA_USE_QT_SCALING=1 in the environment, then clear the Plasma SVG cache (`rm ~/.cacheplasma*) and then restart plasmashell and kwin (`plasmashell --replace` and `kwin_x11--replace`) and let me know if the Plasma X11 session suddenly looks like it does in the Wayland session?
Comment 8 Bug Janitor Service 2020-08-08 04:33:08 UTC
Dear Bug Submitter,

This bug has been in NEEDSINFO status with no change for at least
15 days. Please provide the requested information as soon as
possible and set the bug status as REPORTED. Due to regular bug
tracker maintenance, if the bug is still in NEEDSINFO status with
no change in 30 days the bug will be closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

If you have already provided the requested information, please
mark the bug as REPORTED so that the KDE team knows that the bug is
ready to be confirmed.

Thank you for helping us make KDE software even better for everyone!
Comment 9 Bug Janitor Service 2020-08-23 04:33:08 UTC
This bug has been in NEEDSINFO status with no change for at least
30 days. The bug is now closed as RESOLVED > WORKSFORME
due to lack of needed information.

For more information about our bug triaging procedures please read the
wiki located here:
https://community.kde.org/Guidelines_and_HOWTOs/Bug_triaging

Thank you for helping us make KDE software even better for everyone!
Comment 10 Tore Havn 2020-09-05 23:48:44 UTC
Seems that things work after I cleared the cache. There's still differences in scaling (especially with Latte dock), but it seems that this problem itself is not real.

Setting status to Resolved Fixed to make it clear that this is properly resolved.
Comment 11 Nate Graham 2020-09-07 10:47:15 UTC
That makes sense. This should be automatically fixed in Frameworks 5.74 BTW.

The difference in scaling is probably Bug 356446. If you set PLASMA_USE_QT_SCALING=1 on X11, things will probably look roughly similar scale-wise (better on Wayland though due to lack of a zillion minor glitches).