This is one piece of the puzzle to solve: https://bugs.kde.org/show_bug.cgi?id=412189
On my laptop, a Lenovo ThinkPad T580,
structureValue(st, "object.id") returns the empty string.
When Kamoso tries to switch the camera here it compares
Because both are the empty-string, the camera device is not changed.
Please let me know if there is a better way to fix this.
Part 2 of this bug is harder to fix.
The dropdown value of the combobox is hidden behind the settings panel. I'll try to figure out how to bring it forward, but I'll submit that is a different request.