Cannot open context menus via touch input

[JaneSmith]

One of the devices I am using Syncthing GTK on is a tablet, running Fedora Silverblue. I have installed Syncthing GTK via the Flatpak package on Flathub.

As a tablet, all input is done through the touchscreen. Typically, I can access context menus / right-click menus by pressing and holding on the screen until the menu appears. For example, this works in GNOME Files, where the right-click menu will appear after a second of holding. Unfortunately, this doesn't seem to work in Syncthing GTK. As a result, I am unable to manipulate my shared folders or devices, giving me very limited functionality from the application.

Steps to reproduce:

1. Open Syncthing GTK.
2. Use a touchscreen to long press on a folder or device heading.

Expected result:

The context menu should appear.

Actual result:

Nothing happens until letting go of the touchscreen, at which time the folder or device just collapses/expands as if it was simply clicked.