Use of stripslashes hurts CSS

[glueckpress]

The use of stripslashes() on any textarea of WP Rocket’s settings as well as for the output of the new critical path CSS option breaks any notation of glyphs in critical path CSS, leading to broken design on the front-end of a website:

element:before{content:'\f300'}

gets stripped to:

element:before{content:'f300'}

We need to find a way around stripping all the backslashes and leave those inside of CSS rules intact.