(1) Take any document and insert a formula.
In the command window type " sope ", including the quotes, result:
" sope "
(2) Set the cursor in front of it at the first position and write an m, result:
m" sope "
(3) Click between s and o for to add an l. Notice, that the cursor is not shown
between s and o but between o and p.
(4) Pless l. Notice that the l is inserted between s and o. The mouse click is
used for editing, but the cursor is shown at wrong position.

This is an severe error in the UI. Mixing text parts into formulas is often
needed in Draw and Impress, because the text box cannot include a formula, and
so using text in a formula is the only way to combine formula and text.

Although this is an error in the command window of the formula editor, it might
be connected to issue 113493, which describes a similar defect for text boxes.

I see the error first in DEV300m83, it is OK in m82.