very strange 418 error on tile loding

Dear all, I have since today a 418 error on tile loading from my developmment environnment (linux / chrome) :

Always the same dev env. and same code since more than 3 years, never got this 418 error Never done any bulk copy, tile only called from leaflet OpenStreeMap displayed on the leaflet map corner with link to https://www.openstreetmap.org/copyright

in the dev console of chrome if I click on one tile, by example : a.tile.openstreetmap.org/17/65680/44813.png:1 , the tile opens in chrome !

chrome seems up2date :Version 103.0.5060.114 (Build officiel) (64 bits) Same 418 error when I try using a vpn

Still works fine with firefox from my PC Still works fine if I put my code on a server on cloud

Any suggestion ?

Kindest regards