Re: [Libguestfs] another GTK3 regression...

On Wed, Sep 28, 2022 at 02:01:11PM +0200, Laszlo Ersek wrote: > (this reproduces at commit 0687cea6a86e; IOW the regression is not from > the recent GTK-related patches, but due to building p2v with GTK3. as > opposed to GTK2) > > In the first dialog, when the Test Connection button is clicked, a > spinner is supposed to be shown to the left, while p2v communicates via > v2v over ssh. This spinner is seen when running virt-p2v directly, but > not when running virt-p2v from a VM (using either a Live CD, or the > "run-virt-p2v-in-a-vm" makefile target). > > This difference is not seen when virt-p2v is built with GTK2; in that > case, *both* scenarios (direct & VM) show the spinner properly. > > I don't have an idea what the cause is. I vaguely suspect it could be > related to the windowing environment (window manager) in use. It pretty > much looks like a GTK3 bug to me; whatever the windowing environment, > the spinner should either be there or not. (It's possible that we have a > virt-p2v bug, of course, but why isn't the symptom consistent then? GTK3 > should not have a dependency at all on the Window Manager.) There certainly are dependancies on both the window manager, and the desktop system (X11 vs wayland). There's a huge set of features that widget toolkits can negotiate with window managers, and each window manager supports a different set of extensions, just one example being support for client side window decorations. In theory GTK should adapt to expose the same functionality to users whereever possible but there are certainly edge cases where this doesn't work, and bugs will certainly be present for more obscure combinations like X11 + any non mainstream window manager. It is also not surprising to see a differnce from GTK2 to 3, as it radically changed under the hood, most notably with native Wayland support.