227360 2021-06-24 10:00:54 -0700 WebKitGTK fails to handle some keypresses when built with the GTK Quartz backend on macOS 2021-09-02 20:37:21 -0700 1 1 1 Unclassified WebKit WebKitGTK WebKit Local Build Mac (Intel) macOS 10.14 NEW P2 Normal --- 1 discuss webkit-unassigned berto bugs-noreply cgarcia clopez ews-watchlist gustavo oldest_to_newest 1772326 0 discuss 2021-06-24 10:00:54 -0700 # What's affected Browsers built with WebkitGTK and the GTK Quartz backend. I've noticed this behavior while trying out the Nyxt browser[1] on macOS. # How to reproduce 1. Build and run the MiniBrowser 2. Open any website with a text input field 3. Type "abc" into the input field # What's expected to happen "abc" is displayed in the input field. # What actually happens Nothing. # The cause The problem is caused by the input method handling code in WebKitGTK. When using the Quartz backend, WebKit throws out some text inputs that are passed through GTK's input method interface. My understanding is that GTK based input method systems may choose to consume keypress events in order to compose non-alphabetic text[2][3][4]. The consumed keypresses are processed by the input method systems as part of the "preediting" phase, and the final composed text is passed back to WebKit through a "commit" signal[5]. There is a complication here however, because different input method implementations consume keypresses differently. Based on what I've observed, the iBus input method on Linux doesn't consume simple alphabetical inputs and leaves WebKit to handle keypress events directly. On the other hand, GTK's Quartz backend on macOS consumes simple alphabetical inputs[6] and immediately fires the "commit" signal, accompanied by a "preedit-changed" signal[7][8]. This in turn causes WebKit to ignore the keypress event[9] *and* the "commit" signal fired by GTK[10]. And hence the issues. [1]: https://nyxt.atlas.engineer [2]: https://github.com/WebKit/WebKit/blob/a705747a1538dbb82ebc30f11d5413e67a0fa758/Source/WebKit/UIProcess/API/gtk/WebKitWebViewBase.cpp#L1101-L1102 [3]: https://github.com/WebKit/WebKit/blob/0c141f987eda765a8cc36509147542c160c52d0d/Source/WebKit/UIProcess/API/glib/InputMethodFilter.cpp#L99 [4]: https://github.com/WebKit/WebKit/blob/8afe31a018b11741abdf9b4d5bb973d7c1d9ff05/Source/WebKit/UIProcess/API/gtk/WebKitInputMethodContextImplGtk.cpp#L178 [5]: https://developer.gnome.org/gtk3/stable/GtkIMContext.html [6]: https://github.com/GNOME/gtk/blob/77f32a69c0a35ffd3a1a542a6057c1c6d13c793d/gdk/quartz/GdkQuartzView.c#L239-L240 [7]: https://github.com/GNOME/gtk/blob/77f32a69c0a35ffd3a1a542a6057c1c6d13c793d/modules/input/imquartz.c#L163-L164 [8]: https://github.com/GNOME/gtk/blob/77f32a69c0a35ffd3a1a542a6057c1c6d13c793d/modules/input/imquartz.c#L206 [9]: https://github.com/WebKit/WebKit/blob/8afe31a018b11741abdf9b4d5bb973d7c1d9ff05/Source/WebKit/UIProcess/API/glib/InputMethodFilter.cpp#L116-L118 [10]: https://github.com/WebKit/WebKit/blob/8afe31a018b11741abdf9b4d5bb973d7c1d9ff05/Source/WebKit/UIProcess/API/glib/InputMethodFilter.cpp#L326-L327 1772333 1 432180 discuss 2021-06-24 10:09:55 -0700 Created attachment 432180 Patch 1772336 2 ews-watchlist 2021-06-24 10:11:01 -0700 Thanks for the patch. If this patch contains new public API please make sure it follows the guidelines for new WebKit2 GTK+ API. See https://trac.webkit.org/wiki/WebKitGTK/AddingNewWebKit2API 1772343 3 discuss 2021-06-24 10:21:29 -0700 I've uploaded a patch that I'm considering applying to the downstream macOS build of WebKitGTK in the Nix package manager for the time being. It seems to fix the problem, but I'm not too sure whether this is a good idea or not. Would applying this patch have any obvious unintended side effects? Any help would be appreciated. 1790042 4 clopez 2021-09-02 20:37:21 -0700 (In reply to discuss from comment #3) > I've uploaded a patch that I'm considering applying to the downstream macOS > build of WebKitGTK in the Nix package manager for the time being. It seems > to fix the problem, but I'm not too sure whether this is a good idea or not. > Would applying this patch have any obvious unintended side effects? Any help > would be appreciated. It seems it has unintended side effects. As far as I can see this patch made the WebKitGTK API tests to fail on the CI, check the red bubble above -> https://ews-build.webkit.org/#/builders/34/builds/38608 432180 2021-06-24 10:09:55 -0700 2021-06-24 10:09:55 -0700 Patch bug-227360-20210625020953.patch text/plain 2071 discuss U3VidmVyc2lvbiBSZXZpc2lvbjogMjc5MTcyCmRpZmYgLS1naXQgYS9Tb3VyY2UvV2ViS2l0L0No YW5nZUxvZyBiL1NvdXJjZS9XZWJLaXQvQ2hhbmdlTG9nCmluZGV4IGUxMDdjZmUzYzA4MWVjMTAz ODE5NzkyOWVmMzFjZTNmNjA1MzNjMjMuLmI4NzJlM2YxMWJmNWFiZDZkM2NkZTU0YjVhMDVmNmYw M2JmYzEyNDAgMTAwNjQ0Ci0tLSBhL1NvdXJjZS9XZWJLaXQvQ2hhbmdlTG9nCisrKyBiL1NvdXJj ZS9XZWJLaXQvQ2hhbmdlTG9nCkBAIC0xLDMgKzEsMTYgQEAKKzIwMjEtMDYtMjQgIFNobyBZdWhh cmEgIDxnaXRAbWlkY2hpbGRhbi5vcmc+CisKKyAgICAgICAgV2ViS2l0R1RLIGZhaWxzIHRvIGhh bmRsZSBzb21lIGtleXByZXNzZXMgd2hlbiBidWlsdCB3aXRoIHRoZSBHVEsgUXVhcnR6IGJhY2tl bmQgb24gbWFjT1MKKyAgICAgICAgaHR0cHM6Ly9idWdzLndlYmtpdC5vcmcvc2hvd19idWcuY2dp P2lkPTIyNzM2MAorCisgICAgICAgIFJldmlld2VkIGJ5IE5PQk9EWSAoT09QUyEpLgorCisgICAg ICAgIE5vIG5ldyB0ZXN0cyAoT09QUyEpLgorCisgICAgICAgICogVUlQcm9jZXNzL0FQSS9nbGli L0lucHV0TWV0aG9kRmlsdGVyLmNwcDoKKyAgICAgICAgKFdlYktpdDo6SW5wdXRNZXRob2RGaWx0 ZXI6OmZpbHRlcktleUV2ZW50KToKKyAgICAgICAgKFdlYktpdDo6SW5wdXRNZXRob2RGaWx0ZXI6 OmNvbW1pdHRlZCk6CisKIDIwMjEtMDYtMjMgIENvbW1pdCBRdWV1ZSAgPGNvbW1pdC1xdWV1ZUB3 ZWJraXQub3JnPgogCiAgICAgICAgIFVucmV2aWV3ZWQsIHJldmVydGluZyByMjc5MTA0LgpkaWZm IC0tZ2l0IGEvU291cmNlL1dlYktpdC9VSVByb2Nlc3MvQVBJL2dsaWIvSW5wdXRNZXRob2RGaWx0 ZXIuY3BwIGIvU291cmNlL1dlYktpdC9VSVByb2Nlc3MvQVBJL2dsaWIvSW5wdXRNZXRob2RGaWx0 ZXIuY3BwCmluZGV4IGU3YmQ2YTFlMGZmNjczMDg5ZDM3ODI2NGIwZGZiNTg0ZTVlZmVmODQuLmE4 ZGVlYzY0NGUzODljMDEzNGNiZGFhNDI4Y2FlOWQ2NzU3Y2QxYjkgMTAwNjQ0Ci0tLSBhL1NvdXJj ZS9XZWJLaXQvVUlQcm9jZXNzL0FQSS9nbGliL0lucHV0TWV0aG9kRmlsdGVyLmNwcAorKysgYi9T b3VyY2UvV2ViS2l0L1VJUHJvY2Vzcy9BUEkvZ2xpYi9JbnB1dE1ldGhvZEZpbHRlci5jcHAKQEAg LTExMywxMCArMTEzLDYgQEAgSW5wdXRNZXRob2RGaWx0ZXI6OkZpbHRlclJlc3VsdCBJbnB1dE1l dGhvZEZpbHRlcjo6ZmlsdGVyS2V5RXZlbnQoUGxhdGZvcm1FdmVudEsKICAgICBpZiAoIWhhbmRs ZWQpCiAgICAgICAgIHJldHVybiB7IH07CiAKLSAgICAvLyBTaW1wbGUgaW5wdXQgbWV0aG9kcyB3 b3JrIHN1Y2ggdGhhdCBldmVuIG5vcm1hbCBrZXlzdHJva2VzIGZpcmUgdGhlIGNvbW1pdCBzaWdu YWwgd2l0aG91dCBhbnkgcHJlZWRpdCBjaGFuZ2UuCi0gICAgaWYgKCFtX2ZpbHRlcmluZ0NvbnRl eHQucHJlZWRpdENoYW5nZWQgJiYgbV9jb21wb3NpdGlvblJlc3VsdC5sZW5ndGgoKSA9PSAxKQot ICAgICAgICByZXR1cm4geyBmYWxzZSwgV1RGTW92ZShtX2NvbXBvc2l0aW9uUmVzdWx0KSB9Owot CiAgICAgaWYgKCFwbGF0Zm9ybUV2ZW50S2V5SXNLZXlQcmVzcyhrZXlFdmVudCkpCiAgICAgICAg IHJldHVybiB7IH07CiAKQEAgLTMyMiwxMCArMzE4LDYgQEAgdm9pZCBJbnB1dE1ldGhvZEZpbHRl cjo6Y29tbWl0dGVkKGNvbnN0IGNoYXIqIGNvbXBvc2l0aW9uU3RyaW5nKQogCiAgICAgYXV0byog d2ViVmlldyA9IHdlYmtpdElucHV0TWV0aG9kQ29udGV4dEdldFdlYlZpZXcobV9jb250ZXh0Lmdl dCgpKTsKICAgICBBU1NFUlQod2ViVmlldyk7Ci0gICAgaWYgKG1fZmlsdGVyaW5nQ29udGV4dC5p c0FjdGl2ZSkgewotICAgICAgICBpZiAoIW1fZmlsdGVyaW5nQ29udGV4dC5wcmVlZGl0Q2hhbmdl ZCAmJiBwcmVlZGl0V2FzRW1wdHkgJiYgbV9jb21wb3NpdGlvblJlc3VsdC5sZW5ndGgoKSA9PSAx KQotICAgICAgICAgICAgcmV0dXJuOwotICAgIH0KICAgICB3ZWJraXRXZWJWaWV3Q29uZmlybUNv bXBvc2l0aW9uKHdlYlZpZXcsIG1fY29tcG9zaXRpb25SZXN1bHQpOwogICAgIG1fY29tcG9zaXRp b25SZXN1bHQgPSB7IH07CiB9Cg==