Redefine tab as 4 spaces in Gitlab CE

See this huge identations is painful (for me). Is there a way to set tab size to 4 spaces.

This picture is taken from local Gitlab CE server with minimal customization. I think tabsize 8 spaces is default.

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How do I change a tab to 4 spaces in vim?

All the above works for new files. To convert tabs to spaces in the currently opened file in Vim, enter the Normal mode by pressing Esc key. Now use the retab command by pressing the ':' (colon) character and Vim will convert the existing tabs to spaces.

Is tab 4 a space?

Answer. In most code editors, tabs are not the same as 2 spaces or 4 spaces by default. A tab is stored differently than spaces in the code. Tabs can be seen as a big “jump” in the text, while spaces are always 1 space each.

Go to Settings -> Preferences -> Behavior and set Tab width