TYPO3 Core

So, you are getting a fatal error if accessing the install tool? This is only possible if extension have weird and not core supported hacks in ext_autoload. Looking at ext:fluidcontent and ext:flux on github, both don't contain such a hack anymore - maybe an update of these extensions is needed.

Can you tell us if this is still viable? Thank you!

Hi Jeppe. Do you think this could be closed? Have you tried with the latest version of Flux? Thank you

No feedback within the last 90 days => closing this issue.

If you think that this is the wrong decision or experience this issue again, then please write to the mailing list typo3.teams.bugs with issue number and an explanation or open a new ticket and add a relation to this ticket number.