What browser am I using ?

[Sampei Nihira]

The test below with Pale Moon is OK:

https://www.whatismybrowser.com/

Basilisk is recognized as Firefox 52.9.
Out of date.

[zirii]

What do you expect? the website is getting a user-agent "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:52.9) Gecko/20100101 Goanna/4.1 Firefox/52.9 Basilisk/20180905" and doesn't recognize it, because Basilisk is about 0% of the market share. so they just don't have this browser on their radar and just see firefox 52.9.0 - which is indeed outdated since sept.5.

[therube]

and doesn't recognize it, because Basilisk is about 0% of the market share. so they just don't have this browser on their radar

Nothing to do with "recognizing" or "radar".

They are simply reading the useragent that Basilisk is reporting.
And Basilisk is reporting 52.9, so that is what it tells you.

As far as "outdated", well, whatever that is supposed to mean.
IOW, unless your browser is actually outdated, then it means nothing.

[Giraffe]

Just tried it with PM 28.0.1 with UA Mozilla/5.0 (Windows NT 6.1; rv:59.0) Gecko/20100101 Firefox/60.0 and out-of-date; changed to
Mozilla/5.0 (Windows NT 6.1; rv:59.0) Gecko/20100101 Firefox/62.0 and now up-to-date. Whoopee!

[Sampei Nihira]

I changed:

general.useragent.compatMode.version"

value 52.9

to

62.0.

Now it's OK.

If you set:

general.useragent.compatmode.firefox to false

Basilisk pass the test.
But there is a contra-indication the old Google web-page is displayed.