I did not find any good answer to this question so I share what I found and works
if you want to remove all the google analytics terms from an URL, you mostly want to keep the other parameters and get a clean valid URL at the end
url = url.replace(/(\&|\?)utm([_a-z0-9=+\-]+)/igm, "$1");
with a url like this
https://www.somewebsite.fr/produit/yi-camera-3600-noir-vr-33705370/offre-81085802?utm_source=325483&utm_medium=affiliation&utm_content=catalogue-RDC&awc=6901_1530705916_88ef12642ad61dfc5239ba01bbbe5249
you will get this https://www.somewebsite.fr/produit/yi-camera-3600-noir-vr-33705370/offre-81085802?&&&awc=6901_1530705916_88ef12642ad61dfc5239ba01bbbe5249
this url is already valid but we have some dupe & signs if you remove the $1 …