Hi, i am unable to login through the redbox given below in the screenshot after upgrading from 3.5.2 to 3.5.3 i am able to login through only greenbox given in the screenshot. Kindly help me resolve.
It appears a new security measure was added to Moodle and your theme is not compatible. Adding the following line to config.php should resolve it until your theme is fixed.
$CFG->disablelogintoken = true;
New Moodle Doc helps explain the issue. A new login token is required for better security I am guessing.
https://docs.moodle.org/dev/Login_token
Fordson theme update 15 fixes this issue for our theme