Custom CSS does not show – Enfold.css corrupted on DEV > PROD transfer

Hi guys,
I found an old thread filed at
https://kriesi.at/support/topic/quick-css-issue/
My case shares sympthoms, and one of the smallest tricks mentioned there worked fine.

A WP website runs smoothly on DEV, but when transferred to PROD it lacks most of the styling, totally unlovely.

Since this solution is available for any user level (as long as you can manage an FTP client) I opened this thread as an extension to the 2017 one.
I was developing my professional website on server A, and ended up at server B as production environment.
Both shared PHP v7.2 and overall settings, so after initial CSS fail I cleared this one.
Next step was jumping here :) After reading the 2017 thread, I opted for beginning from the easiest solid suggestion.
In my case the solution was renaming my Enfold_child.css by appending extra letters to the file extension, then (with the Child theme settings page already open and custom CSS already written in its field) just pressed “Save changes”.
Immediately jumped on the FTP client, F5 and no surprise, a new CSS file was created from scratch
Then just F5 on the public page tab and website just came to its actual look&feel.
Hope this is useful to anyone.