I've now found that if I get to the main PBO site and then select 'forum', I get it in normal form (which I'm viewing now). Must be something with my personal setup.
Interestingly, last week I had a glitch with "Scuttlebutt" as my browser defaulted to the YM website when I clicked on it. Probably something to do with the server, I guess as the problem went away after a day or so.
They had a message up that something broke on a routine upgrade recently...
I wonder if there are some "little" issues around navigation etc. They might not even know about them.
I have some long standing oddity where some html code shows like it only half loads the page. I think that is an issue here though with a network / proxy issue
There are several threads here http://www.ybw.com/forums/forumdisplay.php?83-Forum-News-and-Feedback about access problems in the last week. It looks as though they are moving to new forum software but keeping the old forums running meanwhile. Some of us got caught in the new Xenforo system and it wouldn't let go. All seems back to normal now for me on a laptop.
Same problems for me with navigation around the forum. I thought it might have been Ubuntu 18 newly added. Glad to hear others have the same problem. ol'will