• I have searched the issues of this repository and believe that this is not a duplicate.

Reproduction link

Steps to reproduce

Update @height-base variable to something more (for example 50px). When you add a extra action with a button in Page Header, the header is higher than a version without extra button

What is expected?

Header is always the same height and can fit a regular-sized button in the extra parameter

What is actually happening?

The header jumps if you add button with updated height in the extra parameter

Environment	Info
antd	4.16.13
React	17.0 (not related)
System	Linux
Browser	Chrome

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What I did locally to mitigate the issue is add @height-base in

which resolved the issue (the 32px is default height-base, so I assumed it should be that - but I'm not certain)