Technicolor TG582n can't login if dsl down

[#1]

Hi.  If I try to log into the admin account on the TG582n router when dsl is down, the login isn't accepted.  Instead, I just get empty edit boxes again, and NO message saying "invalid username or password".  A look online give ma a YouTube video of the same thing happening.  When DSL is up, it works OK.  If I deliberately  drop the connection while already logged in, I can view other pages as usual.  Also, when browsing and DSL drops, I used to get the admin login screen when I clicked a link.  If I try Internet Explorer instead of FireFox, I can log in normally regardless of DSL is down or not.  Same login problem happens on two old laptops as well.  Is this a router fault, firefox fault or both?  In IE, if DSL is down and I try a website, it still doesn't bring up the login page but instead says "this page is unavailable" (or something like that).

[#2]

This sounds like a browser issue. What versions of internet explorer and Firefox are you running ?

[#3]

FireFox 56.0.1 64-bit

IE 11.0.9600.18816

On my desktop PC, I'm running Windows 7.  On the laptops it was XP, so I rarely use them on the net these days.  They are actually netbooks, so very very slow!

[#4]

Bring your DSL link up, then get to the admin page.  From there disable @"Web browsing interception"

https://www.intelligentpos.com/uk/support/faqs/how-disable-web-browsing-interception-technicolor-rou...

That should (hopefully) fix the problem.

[#5]

Thanks, I just tried it and it worked.  Presumably then, FireFox in it's latest version is doing something that screws up the "interception", whereas IE doesn't?  I presume this means that if DSL drops out while browsing, I won't get the login page appearing as it used to?  It wasn't much use anyway - you just had to wait for it to automatically connect again.