Help with webfilter Regex to allow Steam

The one I tried is ^https?://[A-Za-z0-9.-]+\.steamserver\.net

and 

^https?://([A-Za-z0-9.-]*\.)?steamserver\.net/

I entered these only into Webfiltering Profiles, Filter Actions, Websites, Allow these Websites. But it's not working.

Edit: I think what the issue is that I have to add Steams' TCP/UDP ports to the "allowed services" tab of the Webfiltering Options>MISC tab by creating service definitions.

The one I tried is ^https?://[A-Za-z0-9.-]+\.steamserver\.net

and 

^https?://([A-Za-z0-9.-]*\.)?steamserver\.net/

I entered these only into Webfiltering Profiles, Filter Actions, Websites, Allow these Websites. But it's not working.

Edit: I think what the issue is that I have to add Steams' TCP/UDP ports to the "allowed services" tab of the Webfiltering Options>MISC tab by creating service definitions.

There should be only a couple of things you need.  I run Steam pretty much daily.  

Web filtering:

Steam does need to have some ports opened.  I have three service definitions:

For any gaming ports that I need to open, I create a 'Gaming' group and put all of the ports that I have to open in that group, then add that group to the Firewall Rules.  Just keep it organized. ;)

This should be all you need to run and play in Steam.  If you still run into issues, you can create a Network definition for Valve/Steam (155.133.253.0/24) and add it to your Transparent Skip Lists

thank you. I also read the tutorial from Steam which has a list of the ports used and added them all to the Allowed Target Services.

Still,

Ultimately it seems that the Steam interface will only log me online if SSL scanning is bypassed for the regex entry in Webfilerting exceptions:

^https?://([A-Za-z0-9.-]*\.)?steamserver.net

Otherwise I get this;

Where are you getting steamserver.net?  Is that in their tutorial or someplace else?  I've never seen that name come across any of my filters when I was looking at this traffic initially and have it nowhere in my setup.

I may not have ever seen it either because decrypt and scan isn't used in my environment.

It was in my webfiltering log that I posted above:

Here is an example of my webfilter log:

2022:10:15-16:47:55 XXXXXXX httpproxy[9709]: id="0002" severity="info" sys="SecureWeb" sub="http" name="web request blocked" action="block" method="CONNECT" srcip="192.168.1.30" dstip="" user="" group="" ad_domain="" statuscode="403" cached="0" profile="REF_DefaultHTTPProfile (Default Web Filter Profile)" filteraction="REF_DefaultHTTPCFFAction (Default content filter action)" size="2646" request="0xe6442e00" url="">ext1-ord1.steamserver.net:27021/" referer="" error="Target service not allowed" authtime="0" dnstime="0" aptptime="0" cattime="0" avscantime="0" fullreqtime="294726" device="0" auth="0" ua="" exceptions=""

It just happens to be one of the required ports that Steam uses:

That port is in my example above, as part of the three ports that have to be open for it to work correctly. It's looking for that port to be open in your filter it appears to me.  You don't need the steamserver.net address.