Interference inside Studio 2021 between "Add new term" and the "Editor"

When marking a term in both source & target segments + F2, the TermBase window (left-hand side) opens. The new entry is shown, so far so good. But two movements within a subfield of either source or target term in this window are *not* executed therein, but - strange enough - in the *Editor* window. These two are: ctrl + pos1 (to go to first position in that field) and shift + Enter (to add an empty line). This happens on both my machines.

When doing ctrl + pos1 inside the TM-window within Studio 2021, this step is executed, as said, in the Editor, meaning that the cursor leaps back to segment 1 of my present translation.

When doing shift + Enter in a field in the TM-window, this step is executed, as said, in the Editor, meaning that an empty line is inserted in the active target segment of my present translation.

Supplementary info: both updates for respect. MultiTerm (SDL MultiTerm 2021 SR1 -16.1 .1.541) and Studio (SDL Trados Studio 2021 SR1 - 16.1.3.4096) have been installed, but to no avail as to this short circuit happening between these two different windows.

Is there any possibility of shunning / repairing these two dysfunctions?