Cannot login to backend after upgrade to 1.9.27

[arminfuerst]

After upgrading from 1.9.26 to 1.9.27, I cannot login to the backend anymore. When using the correct credentials, I always get the message "Errors during login!".
I tried to set:
$phpwcms['session.cookie_httponly.off'] = true;
as well as
$phpwcms['session.cookie_samesite'] = 'None';
but there were no changes in the behavior. I don't get any error in the web server's logs.
Upgrading directly to 1.9.30 doesn't work either.

[arminfuerst]

I found a workaround:

• After upgrading, I always restart the webserver.
• Refreshing even with <Shift><Reload> did not help.
• I noticed, logging in is possible in a private window.
• I then made a trivial change in login.php, after this, the login was also possible.
• I then upgraded to 1.9.28 and the login was still possible.
• As a last step, I upgraded to 1.9.29 and 1.9.30 and the login remains working.

[q23]

Why do you close this issue? Workaround is not the best solution
What is the trivial change in login.php?
Since 1.9.x is better to clear cookies after update and set base_href true

[arminfuerst]

Why do you close this issue? Workaround is not the best solution What is the trivial change in login.php? Since 1.9.x is better to clear cookies after update and set base_href true

I closed it because I wouldn't be able to retest any solution. I don't know whether this was related to cookies. I would be fine if the issue will be reopened, but I doubt I could assist in solving this or confirming a solution.