When many extensions are present, buttons on main toolbar are on the left rather than centered

[RRosio]

Original Issue Opened by @ManPython in Notebook Repository

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Issue Title

If many extension, then panel board with btns is not in center but on left that made disonanse

Describe the bug
If many extension, then panel board with btns is not in center but on left that made disonanse

To Reproduce
Steps to reproduce the behavior:

Screenshot in original issue:

Expected behavior
It should be in center, or give option for whole wide size width as screen allow.

Screenshots

Screenshot in original issue:

Desktop (please complete the following information):

OS: [e.g. iOS]
Browser \ FF 109.0.1
Version [e.g. 22]
Additional context
Add any other context about the problem here.