Updating after customizing!

[elkebirmed]

I'm confused about the customizing and updating operations in Bootstrap.

let's say that i customize some less variables from the customizer page to change colors, sizes ...etc. than i want to update my Bootstrap to the next future version.

have i customize the settings again? because the updates will take me back to the default settings and if i decide to customize it again i should remember my last settings!

let me know about some tips to avoid this hard work, and do an XML file that will be downloaded with the customizer package in order to use it again with newer versions.

[cvrebert]

Duplicate of #9951.