I have done some more 'shallow' investigation about the problem and have found that when you start KStars, EKOS and INDI with the xml files (.xml and .xml.default) deleted, I have the control over the buttons and can change baud rate, can connect, etc...
If I stop INDI and restart it without doing anything (i.e. delete xml's), responsivity is lost, baud rate can't be changed but device may connect, Indiduino Meteo Station would not but Weather Radio does.
If I stop INDI, open a terminal to delete the xml's and restart INDI, responsivity is recovered. So, unless what I tried is a special case, you don't have to stop/quit EKOS or KStars to get responsivity back.
I haven't tried with more that one device but I assume that the problem may lie across all devices specified in the profile.
Hope this helps and I can perform some more tests if needed. The xml files for Weather Radio are attached, renamed to .txt files.
I believe I have a fix for this... both INDI+KStars needs to be updated to GIT for this to work. Please try. I still do not know WHY it happens, I know it happens due to some property removal. When I check INDI, it was an unnecessary removal which is now disabled.
Did a quick check with the Weather Radio driver on INDI stable and INDI nightly. Stable has the responsivity bug (button presses not working as they should), and nightly works fine. My test is not exhaustive though as my nightly system does not have much hardware attached to it. Gotta move hardware from one platform to the other.
Maybe someone who has a system working on nightly could report to confirm.
I'm sorry, I have to report a remaining small glitch!! After having switched to [Ethernet] in "Communication mode" and saved that, the buttons [Serial] [Ethernet] do still not react after the second invocation of an indi-driver. It's reproducible: Launch the "Telescope Simulator", then switch to [Ethernet] with some address and port, save this configuration, disconnect and stop the driver. Upon a new start, the mentioned buttons are dead.
Please note that I'm really glad you found the bug. Perhaps I'm a perfectionist, but in my point of view this part of the drivers has to work flawlessly.