Fish version 4.2.1
OS: Linux
Terminal: Kitty

Third-party customization command had no effect.

Since 4.2.0 (as in it works in 4.1.2) using the mouse to move the cursor has been broken with multi-line commands. Specifically this only occurs after the first command is run in the terminal (as in it moves until you run a command). Clicking to move the cursor doesn't move it between lines, only horizontally on the bottom line, even when the cursor is on a different line, clicking to move it will return it to the bottom line.