This happens if you mess around disconnecting and reconnecting the USB cable.
At least my Saleae Logic clone works that way, because of how Sigrok needs to upload the (open!) firmware (
fx2lafw) on each connection. For best results, avoid disconnecting the USB cable, and restart PulseView after reconnecting.
As I mentioned, always verify you have the correct device selected, before customizing the display. The session files include a reference to the specific hardware used, and if you change the hardware, PulseView tries to revert to the last session stored for that other hardware. Yeah, it is a bit funky.
I wonder how good are the nightly builds and if it is possible to have the nightly coexisting with the stable and using the same sigrok
My "feel" is that the nightly builds are usually OK. You can take a look at the
PulseView git log to see what kind of changes are involved. They seem pretty conservative to me.
If you run Linux, you can use the
nightly AppImage binary (on x86 or x86-64 only though), without affecting a stable/installed sigrok in any way. It is basically a self-contained archived executable and libraries it depends on; it is run directly, it does not "install" anything. See
appimage.org for details.