Use a Shorter User Agent String

[allo]

My Vivaldi currently has the user agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/67.0.3396.102 Safari/537.36 Vivaldi/1.97.1259.3

This contains a lot of information, some unnecessary (Mozilla, AppleWebKit, KHTML, Chrome, Safari are just there because some browser which Vivaldi is based on used it) and a very detailed version . Okay, 1.97 is a dev version, but even this does not need to be communicated to another site.

So why not shorten it to Vivaldi/1.15? I think this snapshot is very similar (for websites) to the latest stable. The micro and nano versions do not matter at all, 1.15 is the only part which could matter, as it is very unlikely that a website would optimize for the difference in 1.15.1000 and 1.15.1001 builds.

It could even more be shortened to just Vivaldi. How many modern sites do you know, which use the user agent string to deliver different content? HTML5 is evolving too fast to use the UA for more than just detecting mobile or not and even this is rare today.

Communicating the exact version does increase the fingerprint (especially in the full fingerprint, which includes micro and nano versions as well as the chromium build) and the security risk for tailored attacks (i.e. for a bug in a certain chromium build).

So let's drop the version numbers or really simplify it.

You can still add the UA-Chooser feature from old Opera versions (or direct users to the corresponding Chromium extensions) for when it is needed, but it should not be needed anymore. Modern sites do feature detection, old sites neither know Vivaldi nor Chromium nor Safari.

[Hadden89]

Vivaldi 1.15 wasn't used -- as a lot of bad sites consider "1.15" as "1.1" or just "1", so old.
I fear sites could reject Vivaldi if other browser strings are not kept.
The UA-chooser was already requested, as it's useful.

[becm]

@allo all data is given to accomodate server side sabotage optimization.
Many sites deliver bad or no content at all if they fail to to determine the (assumed) client feature set.
With luck, they are actually compatible enough to support popular non-Windows-builtin browsers…

A small player called Google (maybe you have heared of them) uses client detection on their services to deliver ever changing site content.
They use a depricated Shadow DOM (v0) interface (where available) since they not yet got arround to optimize for the standardized (v1) version.

The part Vivaldi/1.97. is (in essence) static to accomodate (bad) detection code.
The trailing 1259.3 identifies the actual Chromium version (where needed).