Looking into backtraces provided in: https://gitlab.gnome.org/GNOME/evolution/-/issues/1679#note_1299118 The WebKitWebProcess is busy in the JavaScript call. As it's executed on the main thread the whole process is blocked and any attempt to talk to it (over D-Bus) leads to time outs and the GUI is not updated as well. Would it make sense to call the JavaScript code in a dedicated thread, thus the call can be eventually cancelled from the main process? I can understand the JavaScript code blocks the GUI repaint.