In my word, if I, for example, change the color of a character to blue, and then change the color of other character to grey, and press undo, Word is undoing both actions (not only the last color change). How can I fix this?

You can't do much about it, that's how Undo works (even with Word 2016), at least with colors.

Save the doc after making the first colour change?

I don't know of any option settings that could be adjusted that would change the undo memory increments. I also note that the "Repeat last command" by pressing F4 sometimes disappoints because Word decides to ignore some commands as beneath its level of interest.

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Andrew Lockton
Chrysalis Design, Melbourne Australia

The list of actions that are available for Undo can be found on the Undo drop down.

That said, several users have reported that Undo/Redo behavior has changed recently. This is well worth reporting via File > Feedback > Send a Frown.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional