Set terminal to a fixed size regardless of window and font size

[spodskubka]

Remote Terminal currently adjusts the terminal size (the available rows and columns) automatically based on the size of the application window and the configured font size.

Some applications require specific terminal sizes so many terminal emulators provide the user with the possibility to set (and possibly lock) the terminal width and height to exact values.

Common values seem to be 80×24, 80×43, 132×24 and 132×43, so some terminal emulators provide these as presets with the option to add custom ones.