Automatic noindex tags on versioned docs?

[ChrisRackauckas]

Versioned docs get out of date fast, so it would be nice if we could make sure they aren't indexed to push users towards the stable docs.

[ChrisRackauckas]

Note that with DiffEqDocs we already have canonical tags but still see v5.0 and v2.0 (from 3 years ago!) in the first page of the search, so #1133 isn't quite a fix.

[ChrisRackauckas]

@kanav99

[mortenpi]

Definitely worth looking into. Although one issue that comes to mind is that currently stable/ is just a symlink to the docs of the latest version, i.e. they are literally the same HTML file. So you can't apply noindex to versioned docs without also applying it to stable/.

[fredrikekre]

According to https://www.searchcandy.uk/seo/can-you-use-javascript-gtm-to-add-a-noindex-meta-robots-tag/ it is valid to inject noindex with JavaScript, so that could easily be done.