Sass generates content with a white square?

Hello!
Why Sass compiles here's a white square, instead of "\f13"?
35b7e79e8b5242409538c8e73c2eb2d9.png
Use the built-in File Watcher PhpStorm.

Tried zatestit on sassmeister.com
The result is the same:
60cff0b60917492d91bfdfe40b23bf08.png
July 9th 19 at 14:09
1 answer
July 9th 19 at 14:11
Solution
https://github.com/sass/sass/issues/659

Costs like this:
content: unquote("\"\\f13\"")
Thank you! I used a mixin:

=variable-icon-font($icon-code)
content: #{"\"\\"}#{$icon-code + "\""} - jeffery_Bruen19 commented on July 9th 19 at 14:14

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