apply 'editable_slug' fillter on "Single Slugs" vaules on forum options page

[ramiy]

The Problem: when using non-english charecters on "Single Slugs" fields found on "Options"->"Forum" screen, it doe's not show the right slug.

Recreat The Problem: use special charecters in the slug (using 'tøpæc' will show 't%c3%b8paec').

Solution: using the 'editable_slug' filter.

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The solution for this problem will look like ​this.

RELATED: ​wp#10966, ​wp#16999.

[ramiy]

see ​this example as well.

[Nightgunner5]

This was a problem with standalone bbPress as well. If I had known the fix would be this easy, I could have saved a lot of trouble with workarounds.

[ramiy]

:-)

[johnjamesjacoby]

Nice catch.

[johnjamesjacoby]

(In [3203]) Apply editable_slug filter on form_options. Introduce bbp_form_option() functions to handle the output. Fixes #1526. Props ramly.

[ramiy]

Related #1257.