tldr; Can one get the browser version from the front end without using navigator strings or Client Hints?
So with Google's announcement about freezing the navigator.userAgent string, I've been tasked with going through a bunch of javascript libraries at work in an effort to replace browser sniffing (aka userAgent). I know, I know, we shouldn't use userAgent in the first place because it's a sack of confusion and lies, but I'm inheriting this code and not creating it. Luckily, a bunch of the use cases were dated (IE8-10, PhantomJS, Windows Phone) and I could remove them completely. Others I could figure out which features/intentions the original authors were using and I could swap their conditions for feature detection.
But some of the public facing logic is using navigator.userAgent to figure out the browser version and this has been more challenging to replace because everything I find on the interwebs related to this search points to using one of the navigator properties. I don't know how and why clients care which "version of Firefox a user is on" and I'm awaiting that answer, but in the meantime I'm trying to see if there is a solution out there that can detect browser version on the front end. I'm not restricting the answer to just javascript, if there is a CSS/HTML/JS combination, I'm all for it.
I'm also aware the Google says we should use Client Hints but that requires hitting the server which is out of scope for my task.
Freezing plan via the Google Announcement:
- Different parts of the UA string have different compatibility implications.
- Some parts of it, such as the browser version and the OS version, can be frozen without any backwards compatibility implications. Values that worked in the past will continue to work in the future.
- Other parts, such as the model (for mobile devices) and the OS platform, can have implications on sites that tailor their UI to the underlying OS or that target a very specific model in their layout. Such sites will need to migrate to use UA-CH.
If I am reading the second bullet here correctly, then the version parts of the navigator strings will be frozen and unreliable by Early June 2020.
Again, just so it's clear, I know this should be replace by feature detection, but I don't have full control over our clients and users and I'm just seeing if there is a solution out there. I have a feeling lots of folks will end up trying to solve this problem soon enough.