Regression: Filter values are not decoded

[discordier]

Issue description

When filtering for values containing  , the filter will match against [nbsp] instead.

Apparently we need to decode these special entities.

Ref: #910 (not the same issue but related)

[zonky2]

@discordier maybe a known issue - and we check this at MM ^2.2

[zonky2]

@discordier you can check this at our testcase e.g. with Do[nbsp]enbsp.html

• search Do[nbsp]enbsp => result
• search Do enbsp => no result

maybe we should the same transfer from   to [nbsp] as Contao in the Backend