Just add
-no-browser to your
CSGO launch options and it will completely disable the
MOTD browser.
And now you can use
cl_disablehtmlmotd 0 to not get kicked.
This will also give you an FPS boost and less FPS drops if you used to play with ads.
It will NOT disable your overlay browser that browser is integrated with the Steam client not CSGO.
This parameter will do the same as cl_disablehtmlmotd 1
Source