Squarespace removes UTM query variables when redirecting from non-www to www

Question

I'm setting up some redirects for a client's blog, pointing the old URLs to their new Squarespace site.

Curiously, I noticed some of URL tracking variables were being stripped out during the redirect.

This URL: https://olddomain.com/blog/blogpost-title?utm_medium=email&utm_source=campaign_monitor&utm_campaign=bridgit_newsletter&utm_content=sneakpeak_mar0719

Should have been redirected to: https://squarespacedomain.com/new-blogpost-slug?utm_medium=email&utm_source=campaign_monitor&utm_campaign=bridgit_newsletter&utm_content=sneakpeak_mar0719

But instead it was being redirected to: https://www.squarespacedomain.com/new-blogpost-slug?utm_content=sneakpeak_mar0719

Only some utm_ variables were being removed. If I included ?var_a=test&var_b=test, they would make it through just fine.

The other unanticipated change is that, somewhere in the process, www. got added to the URL.

Looking at the trace, there were actually two redirects happening.

Armed with this new information, I edited the redirect to point directly to the www. version of the squarespace URL. When I did that, it stopped stripping out the utm_ variables.

So I have a few questions:

1. Why would Squarespace want to strip out certain utm_ query variables?

2. Why would it strip those variables only during a non-www to www redirect?

3. Is this a bug Squarespace should fix, or is there a reason for this behaviour?

Answer 1

After having the same issue I reached out to Squarespace support and received the following workarounds:

1. If you use the www version of a link, such as www.yourlink.com vs. yourlink.com, it will prevent the parameters from being stripped.

2. Another option would be to use # instead a ? when creating the utm tracking.

We implemented #1, and it's been working seamlessly.