306993 2026-02-04 14:27:02 -0800 REGRESSION(306485@main): [GTK] Crashes or bad rendering with compositing mode disabled or with hardware acceleration disabled and softGL. 2026-04-20 05:04:07 -0700 1 1 1 Unclassified WebKit WebKitGTK WebKit Nightly Build Unspecified Unspecified RESOLVED FIXED https://bugs.webkit.org/show_bug.cgi?id=305391 https://bugs.webkit.org/show_bug.cgi?id=307077 https://bugs.webkit.org/show_bug.cgi?id=312769 P2 Normal --- 305391 1 clopez cgarcia bugs-noreply cgarcia plampe oldest_to_newest 2178076 0 clopez 2026-02-04 14:27:02 -0800 There are several issues with 306485@main that causes crashes or bad renderings on WebKitGTK when not using the accelerated compositing mode. Problems: A) MiniBrowser Crash with env vars WEBKIT_DISABLE_DMABUF_RENDERER or WEBKIT_DISABLE_DMABUF_RENDERER Enabling any of this two en vars will crash MiniBrowser WEBKIT_DISABLE_COMPOSITING_MODE=1 Tools/Scripts/run-minibrowser --gtk # crash WEBKIT_DISABLE_DMABUF_RENDERER=1 Tools/Scripts/run-minibrowser --gtk # crash B) Bad rendering with WEBKIT_HARDWARE_ACCELERATION_POLICY_NEVER and softGL To reproduce this do the following: 1) Apply this patch to MiniBrowser: diff --git a/Tools/MiniBrowser/gtk/main.c b/Tools/MiniBrowser/gtk/main.c index d3fbb968ee46..6fa773585ec5 100644 --- a/Tools/MiniBrowser/gtk/main.c +++ b/Tools/MiniBrowser/gtk/main.c @@ -1011,6 +1011,7 @@ int main(int argc, char *argv[]) webkit_settings_set_enable_developer_extras(webkitSettings, TRUE); webkit_settings_set_enable_webgl(webkitSettings, TRUE); webkit_settings_set_enable_media_stream(webkitSettings, TRUE); + webkit_settings_set_hardware_acceleration_policy(webkitSettings, WEBKIT_HARDWARE_ACCELERATION_POLICY_NEVER); if (!addSettingsGroupToContext(context, webkitSettings)) g_clear_object(&webkitSettings); 2) Build GTK Release 3) Run the minibrowser like this LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk https://www.meneame.net Instead of rendering the website it renders some rectangles (note: i'm testing on X11). I see this: https://people.igalia.com/clopez/bad_rendering_meneame_regression_306485.png This bad rendering is also reproducible if you navigate a bit and go back and forward, but with this meneame website is 100% reproducible all the times (at least for me) When the issue happens after pressing ongoing back and forth it prints lot of errors on stdout like this: AcceleratedSurface was unable to construct a complete framebuffer AcceleratedSurface was unable to construct a complete framebuffer C) WebProcess crashes at termination To reproduce this apply the same patch than B) (above) and run the minibrowser with softGL also ulimit -c unlimited LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk Then navigate a bit and you will see on the stdout of minibrowser this lines WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. And on coredumpctl you will see coredumps for WebKitWebProcess when the WebProcess is closed to use a new one (due to PSON) Another way to reproduce this is to launch the minibrowser in this URL and close it in just 1-2 seconds after the animation loads LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk https://webglsamples.org/aquarium/aquarium.html 2178089 1 clopez 2026-02-04 14:47:52 -0800 BTW, I double-checked that nothing of this happens if I revert 306485@main locally. 2178269 2 cgarcia 2026-02-04 22:35:35 -0800 Pull request: https://github.com/WebKit/WebKit/pull/57933 2178270 3 cgarcia 2026-02-04 22:40:04 -0800 (In reply to Carlos Alberto Lopez Perez from comment #0) > There are several issues with 306485@main that causes crashes or bad > renderings on WebKitGTK when not using the accelerated compositing mode. Thanks for reporting! > Problems: > > A) MiniBrowser Crash with env vars WEBKIT_DISABLE_DMABUF_RENDERER or > WEBKIT_DISABLE_DMABUF_RENDERER > > Enabling any of this two en vars will crash MiniBrowser > > WEBKIT_DISABLE_COMPOSITING_MODE=1 Tools/Scripts/run-minibrowser --gtk > # crash > > WEBKIT_DISABLE_DMABUF_RENDERER=1 Tools/Scripts/run-minibrowser --gtk > # crash > This should be fixed by PR 57933. > > B) Bad rendering with WEBKIT_HARDWARE_ACCELERATION_POLICY_NEVER and softGL > > To reproduce this do the following: > > 1) Apply this patch to MiniBrowser: > > diff --git a/Tools/MiniBrowser/gtk/main.c b/Tools/MiniBrowser/gtk/main.c > index d3fbb968ee46..6fa773585ec5 100644 > --- a/Tools/MiniBrowser/gtk/main.c > +++ b/Tools/MiniBrowser/gtk/main.c > @@ -1011,6 +1011,7 @@ int main(int argc, char *argv[]) > webkit_settings_set_enable_developer_extras(webkitSettings, TRUE); > webkit_settings_set_enable_webgl(webkitSettings, TRUE); > webkit_settings_set_enable_media_stream(webkitSettings, TRUE); > + webkit_settings_set_hardware_acceleration_policy(webkitSettings, > WEBKIT_HARDWARE_ACCELERATION_POLICY_NEVER); > > if (!addSettingsGroupToContext(context, webkitSettings)) > g_clear_object(&webkitSettings); PR 57933 adds support for passing --hardware-acceleration-policy=always|never to MiniBrowser. > > 2) Build GTK Release > 3) Run the minibrowser like this > > LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk > https://www.meneame.net > > Instead of rendering the website it renders some rectangles (note: i'm > testing on X11). I see this: > https://people.igalia.com/clopez/bad_rendering_meneame_regression_306485.png I can't reproduce this with PR 57933 on wayland, I haven't tried X11, open a new report for this if it still happens on X11. > This bad rendering is also reproducible if you navigate a bit and go back > and forward, but with this meneame website is 100% reproducible all the > times (at least for me) > > When the issue happens after pressing ongoing back and forth it prints lot > of errors on stdout like this: > > AcceleratedSurface was unable to construct a complete framebuffer > AcceleratedSurface was unable to construct a complete framebuffer > > > C) WebProcess crashes at termination > > To reproduce this apply the same patch than B) (above) and run the > minibrowser with softGL also > > ulimit -c unlimited > LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk > > Then navigate a bit and you will see on the stdout of minibrowser this lines > > WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: > Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. > WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: > Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. > WebKitWebProcess: ../src/dispatch_common.c:872: epoxy_get_proc_address: > Assertion `0 && "Couldn't find current GLX or EGL context.\n"' failed. > > And on coredumpctl you will see coredumps for WebKitWebProcess when the > WebProcess is closed to use a new one (due to PSON) > > Another way to reproduce this is to launch the minibrowser in this URL and > close it in just 1-2 seconds after the animation loads > > LIBGL_ALWAYS_SOFTWARE=1 Tools/Scripts/run-minibrowser --gtk > https://webglsamples.org/aquarium/aquarium.html I think I fixed this crash already in https://commits.webkit.org/306709@main 2178291 4 ews-feeder 2026-02-05 00:49:38 -0800 Committed 306842@main (1050700930f6): <https://commits.webkit.org/306842@main> Reviewed commits have been landed. Closing PR #57933 and removing active labels.