Environment

• TeXstudio: 4.2.1
• Qt: 6.2.1
• OS: Windows 10
• TeX distribution: texlive 2018

Expected behavior

When typing on a line with text, existing text should just be pushed to the right.

Actual behavior

The program crashes.

How to reproduce

Simple!

1. Create a line with the text "\include{a}\include{b}" (without the quotes).
2. Place cursor at beginning of that line and start typing "\whatever" (without the quotes). Actually, just the backlash followed by any letters.
3. After a few letters (two, three, five) the program crashes.

In step 1 it must be exactly that. One single \include doesn't work. Neither do \includ or \includE.
texstudio_backtrace1.txt