SKR Pro v1.2 Endstops stay triggered

Hi there, first post since I’m trying to switch from RepRap/DWC to Klipper/Fluidd!
Loving it so far, can’t wait to start printing with input shaping.

Strange thing though; when testing my endstops (very simple switches), connected to PB10 and PE12 (the assigned pins on SKR Pro v1.x). So signal and ground, nothing powered from the 3.3V.
It works, they trigger when they should.

Sadly; the software (either M119 or the Fluidd-tune endstop-thingy) doesn’t “open” the endstops again (when I release the switch) until a board-reset. Even when I disconnect the cable endstop status remains: “triggered”. Adding/removing pull-up doesn’t change this behaviour.

Any suggestions where to look?
I can always go back to sensorless like on DWC, but rather move away from the variance that caused.

image
This remains until board-reset.