In some cases, after an interaction with the first-startup dialog, LO claims it needs a restart. From a user's perspective, that should not happen. The user has not "started" using the app - and is just initially configuring it like the app asked to. And then it tells him it needs to shut down? Lame... :-( I'm not sure if the restart is even actually useful. See also the discussion in bug 166870.
I believe this i due to technical debt in the UI parts of LO. There are a few bugs about this behavior already, where changing a setting requires a restart to take effect. e.g. Preferences > View > Middle Mouse Button > Automatic Scrolling needs restart to take effect - allow to take immediately effect, or prompt restart https://bugs.documentfoundation.org/show_bug.cgi?id=97336 Palette of colors on tool bar 'Color Bar' cannot be set directly; palette chosen elsewhere is used only after restart https://bugs.documentfoundation.org/show_bug.cgi?id=120230 [UI] You must restart LibreOffice so that a new text document gets the new document background color https://bugs.documentfoundation.org/show_bug.cgi?id=164198 Dialogue buttons prematurely change to light/dark colour before theme change OKed or program restarted https://bugs.documentfoundation.org/show_bug.cgi?id=166458 Don't ask for a restart after theme installation https://bugs.documentfoundation.org/show_bug.cgi?id=166870 Pick your poison which of those issues you'd like to set this bug as duplicate to 🙈
I actually think I had done none of these, but I now find it difficult to reproduce. So perhaps this should be closed WFM or INSUFFICIENTINFO.
I fear this is just expected behavior due to one of the known issues irt requiring a restart. Ideally those limitations should be addressed and that will then also result in the startup dialog no longer requiring a restart after applying settings. You can always re-open if you have repro-steps which are independent of the already known restart cases.