XF 2.3 Issue with Administrator Login

[ChadCLund]

XF 2.3.4 (hosted cloud on Xenforo)
admin.php (on Firefox)
The Administrator login is wonky and has been for awhile. I use my credentials, and press the "Administrator Login" button, it posts back but does not process. It is intermittent.
Sometimes, I have to do it 8-10 times in a row for it to take. Then when I get to the admin section, like edit a user, I get an Oops, you are not logged in.
Things that I have tried:
1) remove all caching (and made sure Rocket Loader) on cloudflare.
2) disabled 'Enhanced Tracking Protection' on Firefox
3) checked that I have no other extensions or add-ons enabled for Firefox.
4) cleared out all cache and site data on browser.

This is really becoming annoying and time consuming. Please help!

 

[ChadCLund]

Update: I may have fixed this (for me). It only happens when logging into the admin portal (front end is fine).
In Firefox settings, I had to add a security exception for my website. So, Firefox doesn't like something in there... I will update if the problem appears again.

 

[ChadCLund]

nope...still does it

 

[jeb35]

disable the ad block and see if it works correctly.

 

[ChadCLund]

found it, well an awesome Xenforo guy found it... in the mrrobotos.txt (robots.txt) (which i had customized)
evidently i had a error in it. reverted back to XF default robots.txt
all good

 

[DarkGizmo]

found it, well an awesome Xenforo guy found it... in the mrrobotos.txt (robots.txt) (which i had customized)
evidently i had a error in it. reverted back to XF default robots.txt
all good

I'm having this issue, also in firefox, can you post exactly what you did to fix it? or send me a PM please?