Has the create_function depreciated warning been solved in Wordpress 5.4.2?

It looks like the spam filter might have swallowed your post?! So I'm not really sure what you may have been trying to elaborate on.

To answer the question in your subject, I would say, it's a warning, not an error, so it doesn't need "solving". Deprecated generally means that the code still remains, but will be removed in a future version so it's not recommended to use. I'm sure that WordPress would be aiming to resolve/remove the deprecated code at some point, but it's not really urgent.If it's a problem for you, then perhaps turn down the error reporting level so you only see errors, rather than error and warnings?!

I reckon it's the spam filter. We get hammered by lots of spam so have things locked down a fair bit.

You have an Error In your support forum.  

Perhaps you could try explaining your issue a bit better?! Re search, it's not the greatest search bar, but the one near the top right of the page (just below "My account" and "Logout" when logged in) is definitely there! :)

It's almost useless, and there is no search field either..

Anyway, rather than bitching about our website (which I'm well aware of the issues with) perhaps you could try describing what you've tried.

I'm not at all sure, but my guess is that perhaps you've been running on an older version of PHP? Or perhaps you need an additional dependency (i.e. a PHP module) installed?

Regardless, you'll find lots of sites with troubleshooting info and steps for the fairly common "white screen of death" on WordPress. WordPress themselves note it and other common errors. It sounds like you are trying to enable debugging, which is a good step, but the issue almost certainly isn't anything to do with a warning (warnings are not errors).

Also, if you haven't already, I'd recommend disabling all of your plugins and going back to the default theme. Hopefully that should get your site going again. Then you can enable your plugins and themes, one by one until it breaks. Then you can discuss with the plugin/theme developer what requirement they have and make sure that you are matching them on your server.

If you want more of a hand, you'll need to be a bit more explicit about what you've done, what you've tried to fix it and what the results of that were. TBH, you're not giving me much to work with so far...

Got error 500 now also on your site

I get that you're having a bit of a struggle, but a running commentary of your gripes with our forums isn't really helping me understand your issues, either with the forums or your site... Please provide some useful detail so that I can understand what might be going wrong for you?!

This was the strangest forum I have seen