On this website :
Google Analytics add parameters for cross-domain-tracking to url so a working link like this one
become this, that lead to 404 error
Any tell TYPO3/ RealURL to ignore cross-domain-tracking parameters ?
_gl=11rw78bk_gaODIzMDE2MTIuMTYzODE5MjUyMw.._ga_FVLX79JNXC*MTY0NDQ4NjM1OC40OC4xLjE2NDQ0ODg2MDkuMA..#_ga=2.179165860.1898940241.1644433835-82301612.1638192523
Take a look into configuration what is set for the settings:
$GLOBALS['TYPO3_CONF_VARS']['FE']['cHashExcludedParameters']
$GLOBALS['TYPO3_CONF_VARS']['FE']['pageNotFoundOnCHashError']
In pageNotFoundOnCHashError
you can define if the system throws a 404 when cHash parameters are not valid e.g. when a parameter was added but not handled in cHash. This is happening when an external service adds parameter like Google does in your case.
In cHashExcludedParameters
you can define the parameters that are not used to validate the cHash.
There are 2 options now:
pageNotFoundOnCHashError
to 0 (not so good solution as there won't be a 404 when someone tries to manipulate the parameters)_gl
to the list of cHashExcludedParameters
(better solution as you whitelist the Google parameter and keep your system safe)