Ron Polsley wrote:Are we going to need a spoof for every web page?
Mozilla states: "FireFox 60.0 is no longer supported"
Yes. No. It depends.
I wrote it previously but I'll repeat: You can try the simplest trick - turn off Firefox advertising.
Firefox advertising is built-in User Agent spoofing. It depends on Gecko engine used to built SeaMonkey.
At least it was working this way in past. SM 2.53.x is based on the same engine like Firefox 56 which is "ancient". Developers made a lot of changes while patching and patches were from Fx 60.x, 68.x and some from much newer versions like 78.x ESR. That's why default UA spoof is for "Firefox 60.0" and not "56.0".
But it's "too old" for some "modern" websites. Especially when webdo... webmasters are lazy and requires "latest browser" because website was designed for Google Chrome (sometimes only). I had some situation when website was not working on latest Edge Chromium from MS but without problems on Google Chrome (even one version or two older than latest). More often companies are cheap on support and don't want to deal with "exotic" browsers like SeaMonkey.
Disable Firefox advertising:
Menu -> Edit -> Preferences -> Advanced -> HTTP Networking -> in field "User Agent String" choose "Identify as SeaMonkey"
When needed make site specific override (you know how to) but remember it's made for domain (some websites are using more than one domain for their services).
Of course, you can be lazy too and set general override and you'll always will have spoofed User Agent for all websites.
Oh! And remember that some websites can cause problems even with fake UA because SeaMonkey 2.53.x doesn't have latest fancy features. Such features (aside from security patches) are added almost with every minor version (that's why you should update).