The other point is where I get stuck. I had it enabled (as many others) too and wanted it too keep being enabled like running imscp-reconfigure has done. So the question is why imscp-installer cannot activate it when imscp-reconfigure can.
But at least a note in Errate file would be fine (as you wrote).
Seriously.... If I say, we cannot, that is really because we cannot... Simply put, if the imscp-reconfigure re-enabled the feature, this was simply due to the conditional statement in the code. The behavior was as follow:
Initial state: feature enabled: 1
Running installer script: Feature disabled: 0
Running reconfigure script: Feature enabled: 1
But... due to the conditional statement, if you had executed again:
Running reconfigure script
Result would have been: Feature disabled: 0
Both, the installer and reconfigure script share the same code.
To resume, the bug was here: https://github.com/i-MSCP/imsc…b4736bfe8308552f32deaR519
As you can see, there is a conditional statement leading to value permutation each time it is evaluated. That is fixed now because the statement is now evaluated only when user is answering the question.
Regarding errata file for next version, see https://github.com/i-MSCP/imsc…#alternative-urls-feature 
Again, thank you for your report.
