Rollei SL66: able to fire with magazine dark slide still inserted

My Rollei SL66 just arrived. When doing a little test, I found something quirky: while the magazine dark slide is still inside the film back, the camera can be fired.
I know this is impossible to do on Bronica SQ/Hasselblad/Mamiya RB.

After reading the manual (page 33), I found this:

Fault: the release button blocks
Cause: Magazine slide pushed in
Remedy: Pull out the slide

Click to expand...

Faulty film back/camera body, I guess? But at least:
1. Can fire the camera normally till frame 12, then remove the film magazine as usual.
2. Turning left the shutter button will lock it. Handy for preventing accidentally pressing it.

Mine does the same thing, fires with the dark slide in, but I'll also mention that mine is a "user" and that's a very generous description.

The pin that sticks out from the back moves laterally when the slide is in past the middle, and this blocks a lever inside the body so the shutter can't be release, but those links can be distorted over time and fail to interlock. On mine, if the dark slide is in, I can fire the shutter, but I cannot wind on until I remove the dark slide. At least you can still wind the camera with the dark slide in (?)

itsdoable said:

At least you can still wind the camera with the dark slide in (?)

Click to expand...

I forget to mention that it's not possible on mine. Gotta remove the dark slide before winding.
Which is not an issue on typical Hassy/Bronica SQ/etc. Perhaps I'll buy another film back. And definitely will test with 1 or 2 rolls.

I have two SL66 cameras, neither will fire with a darkslide in (at least not without using unreasonable force).