Haven't bisected, but probably a fallout from https://bugs.webkit.org/show_bug.cgi?id=212324
Created attachment 432895 [details] Patch Patch. I'm not sure about the change in PageClientImpl.cpp, how important is it to have correct x/y for these? I"m also not sure where we get them from for scroll normally, as scroll events don't have coordinates on their own...
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
Committed r279571 (239402@main): <https://commits.webkit.org/239402@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 432895 [details].