libreoffice symbol bars/toolbars load and react with very high latency

[Timo Herbst]

Latency disappears when setting envirionment variable SAL_USE_VCLPLUGIN to 'gen'
(This overrides the autodetect of libreoffice for which desktop the interface has to be renderd and switch to gerneric)

Using Gnome, default for this variable im my case is 'gtk3':
With default SAL_USE_VCLPLUGIN=gtk3 menu bar and toolbars will need more than 10 Seconds to be displayed after application startup - while editor-window is displayed immediately.

While running the application latency between clicking an item and reaction is also abnormal high.
As example: Clicking "Save as ..." results in waiting for some seconds until the "Save as ..."-dialog appears.

This bug does not appear with my systems using intel-igpu. It only affects the machine with amd picasso-igpu

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: libreoffice 1:6.4.3-0ubuntu0.20.04.1
ProcVersionSignature: Ubuntu 5.4.0-31.35-generic 5.4.34
Uname: Linux 5.4.0-31-generic x86_64
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: GNOME
Date: Sun May 24 17:25:42 2020
InstallationDate: Installed on 2020-05-22 (2 days ago)
InstallationMedia: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: libreoffice
UpgradeStatus: No upgrade log present (probably fresh install)

[Heather Ellsworth (hellsworth)]

Thank you for your bug report!

Well we could consider re-adding the SAL_USE_VCLPLUGIN=gen back (like this [0]) but there would be significant testing required on the more common graphics systems, like AMD Radeon and Intel, to make sure this change doesn't affect the performance on those systems.

It seems the AMD Picasso graphics are quite new [1] so this is something that should be fixed eventually but is not a high priority.

[0] https://salsa.debian.org/libreoffice-team/libreoffice/libreoffice/-/commit/89c9b6e690836024d12dd7010bb5609a361119d6
[1] https://www.techpowerup.com/gpu-specs/radeon-picasso.c3286