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This is now happening in Matomo tracker because of https://github.com/matomo-org/matomo/pull/15774/files#diff-1279d666063b65e6d6777f902d11574fR3322-R3330
The cookie now has a lot less parts and different parts.
As part of this issue we need to
@tsteur created https://github.com/matomo-org/matomo-php-tracker/pull/79
Note: doesn't break anything since we don't send those tracking params anymore. Users still need to update. After it's merged, I'll create a PR w/ the changelog info.