aw-webui incorrectly escaping backslashes in regex

[Narice]

This issue was discovered in this forum post which explains what happens if you put a backslash in a regex filter (for example to put a special character as \w)
It was discussed briefly again at the end of this issue on the main repository.
This bug was further discussed in this bug report on the main repository.
This issue makes regex not compliant with the intended regex flavor.