Is it ok to add rel=CANONICAL into the desktop version on top of the rel="alternate" Tag (Mobile vs Desktop version)

[Ideas-Money-Art]

Hi mozzers,

We launched a mobile site a couples months ago following the parallel mobile structure with a URL:m.example.com

The week later my moz crawl detected thousands of dups which I resolved by implementing canonical tags on the mobile version and rel=alternate onto the desktop version. The problem here is that I still also got Dups from that got generated by the CMS.

?device=mobile

?device=desktop

One of the options to resolve those is to add canonicals on the desktop versions as well on top of the rel=alternate tag we just implemented. So my question here:

is it dangerous to add rel=canonical and rel=alternate tags on the desktop version of the site or not? will it disrupt the rel=canonical on mobile?

Thanks

[Ideas-Money-Art]

Thank you Stephanie

[StephanieChang]

Hi Taysir,

Great question! Honestly, I'm not confident what would happen if you add the rel=canonical and rel=alternate tags to the desktop version (and whether that will disrupt the rel=canonical on mobile or not). My advice is to test it out on a few select pages (I would recommend not testing your most important/highest revenue driving pages first, but on less critical pages) and see how the search engines deal with these pages. If the duplicates are removed and traffic to the mobile site isn't affected, then I would start scaling the rel=canonical out on other pages. However if you do see an issue with the combination of rel=canonical and rel=alternate on the desktop version, then it may be worth fixing the CMS, so that it no longer creates these duplicate pages.

Best,

Stephanie