GG 6.0.620-offline (Win10) forgets input lines and definitions

The following behaviour is perfetly repeatable on different computers, including ones that I have never touched in my life. GG version: 6.0.620-offline, but 6.0.581 shows the same behaviour.

Ever since GG 6, I have noted its tendency to make input lines in the CAS view disappear, right down the memory hole. Recent (last year) versions, however, have become downright unusable. Here is a nicely repeatable repro scenario:

Snap15.png shows a brand-new session (GG is set to German, so the actual commands were shown with their German names). The session was opened with (hamburger menu) > File > New, and the perspective chosen was CAS. Function g(x) is defined in line 1, and line 2 computes a definite integral over g(x). The result is correct, but I am surprised that the "integral"-command is not displayed with math typesetting. In fact, it is not even capitalized, as GG normally is wont to do.

Snap16.png shows the same, except that I am getting ready to click what I call the "graph me!"-button.

In Snap17.png, the click is done. As usual, GG assigns an arbitrary name to the result, as it is now a graphed object; surprisingly, however, GG recalled itself to a sense of its duty and properly typeset the integral.

Between Snap17.png and Snap18.png, the following things happened:

1. I typed "h(x):=integral(g(x))" into line 3 (not line 2!) and hit Enter
2. Line 2, with the definition of "a:=" as the definite integral, disappeared
3. Line 3 became line 2
4. "a", apparently still present in the symbol table but now without a definition, was converted to a slider (why? oh, why?)

I can repro this at will on any of the GG6 installations I and the handful of high-schoolers that I tutor have access to. The online versions do not show this behaviour.

Any ideas?

Thanks,

Felix.