Florian6d ago
I was helping an open-source app become more #accessible yesterday and we ran into the problem that it looks like #screenReader Orca has a bit of a tendency to crash when exposed to webkitGTK applications. I've not done Desktop #linux for a long time and have no idea what the workarounds for this would be, does anyone know anyone who might know what's happening here? Do we need to set a random environment variable somewhere or update a specific package so this person can do basic screen reader testing on their app? #tech #openSource #screenReaders #linux #GTK #webdev
Show threadMike Gorse5d ago

@zersiax @pixelate I'm really sorry that you all are running into that.

A couple of questions. Which distribution/version are you running? When you say that Orca is crashing, do you mean that it aborts and needs to be restarted, or is it only failing to read your app but responding to other applications? I think the latter would probably mean that WebKit isn't able to connect to the accessibility bus, so possibly an environment variable isn't being set/transferred properly (I assume it is inside a flatpak?) The former might mean a crash in AT-SPI. https://gitlab.gnome.org/GNOME/at-spi2-core/-/issues/219 is the one crash that I've seen reported recently, and I *think* that I fixed it in at-spi2-core 2.60.0 / 2.58.4 / 2.56.8. If you are, in fact, seeing a crash where Orca is aborting, then I would need to either be able to reproduce it or see a stack trace (if you don't know how to retrieve one, then I'll try to help).

Segmentation Fault Due to Chromium (#219) · Issues · GNOME / at-spi2-core · GitLab

Orca Version Orca version 49.5 (rev d8d6066e7), AT-SPI2 version: 2.58.3, Session: wayland...

GitLab
Show threadFlorian5d ago
@MikeGorse @pixelate my initial understanding was actually wrong, it's not Orca falling over, but rather the application it's talking to. Two Tauri-based apps, Dorion and OpenDeck, exhibit crashing behavior (UI stops responding, then vanishes to only show background) when user tabs through interface with Orca running. I don't think Orca itself crashes but I wasn't there when this happened
Show threadMike Gorse

@zersiax @pixelate I was looking through the commit log the other day and noticed one accessibility-related crash fix post-2.52.1 [1], but I don't know if it is your crash (I know of others). You could of course try filing a bug on bugs.webkit.org if you can get a stacktrace, but I don't think that the Linux accessibility code has been getting a lot of attention lately, and I have several other things on my list of things to do and don't have a lot of time to spend on it either right now. Sorry for not being more helpful.

[1] https://bugs.webkit.org/show_bug.cgi?id=310936

310936 – AX: AccessibilityRenderObject::boundingBoxRect() is missing a null-check on a Node, causing crashes

WebKit Bugzilla
Apr 2 at 12:22amWeb
Show threadPeter Vágner4d ago

@MikeGorse @pixelate @zersiax Although I have no compatible devices, I have built current git main version of opendeck on archlinux with gnome 49 with packages at-spi2-core-git 2.60.0.r5.g814b4d12-1 and orca-git 50.0.r137.gc96d101d4-1, webkit2gtk-4.1 2.50.6-1.

On the opendeck main window I can see these controls in the order of keyboard navigation with the tab key or the object navigation:

  • Initially focused document body element that is causing orca to report nothing when focused. Like the focus changes into a silence when navigating to this. This is not the main issue and my guess is that this is a webkit issue as I can see the same thing with other apps and websites.
  • Navigation with two buttons inside
  • A heading followed by two paragraphs of a text and a Restart button.
  • An input text entry labelled Search actions
  • An interactive list of actions labelled Opendeck.

When using tab key to navigate the whole opendeck app freezes when trying to move from the text entry to the interactive list. Most likelly it also changes the visual appearance as described earlier but I can't verify that on my own. When navigating in a reverse direction by pressing shift+tab navigating from the silent document body element to the interactive list is working fine.

I don't think it's related to this list as I have seen interactive lists in a different apps such as deltachat-tauri which don't cause such a behaviour. However I have seen random freezes like this with the deltachat-tauri app as well and I see this occurence of this issue as a positive thing as I can reproduce such a freeze reliably all the times with opendeck app.

Show threadPeter Vágner4d ago

@MikeGorse @pixelate @zersiax Oh I wanted to just cherrypick this fix on the top of the latest release and test if it fixes this particular case but it does not apply, actually there are more changes to accessibility since last release.
I will try if I can build webkit easily and verify this.

Here is history of commits inside the accessibility folder just out of curiosity: github.com/WebKit/WebKit/commi…

Show threadMike Gorse3d ago
@pvagner @zersiax @pixelate I just installed opendeck and can reproduce the crash. I've either ran into the same crash or a similar one when authenticating a Google account in evolution, but, until now, I hadn't heard of other people running into it, so I thought that it might be somewhat rare. I agree it is bad that some apps are crashing so easily. I've filed https://bugs.webkit.org/show_bug.cgi?id=311427 for it. I don't understand the code very well, but I'll see what I can do.
311427 – AX: Opendeck crashes webkitgtk with Orca running

WebKit Bugzilla