Breakpoint-Point and Debugging-Arrow vanish

I use tests/manual/debugger/simple/simple.pro

I set a breakpoint in line 7104:

On program start, this jumps to line 7112, which is correct:

But when the breakpoint is hit, the red dot vanishes and also the yellow arrow. In the following picture, I would expect both the red dot and the yellow arrow on Line 7112:

In the lower right, in the list of breakpoints, one can see that breakpoint 12 is hit. But is is not shown in the code.