Back Office messed up in Firefox after upgrade to 1.7.8.7

[texxo]

So, i have managed to make an update from 1.7.2.3 directly to 1.7.8.7 last night.

Apart from the hundred of problems with the PHP etc eventually it opens.

I am doing a local upgrade and when i will be sure all is ok i will put in the server.

So, either it is my theme (which is no longer supported but i managed to make it work ok with the 1.7.8.7 - specially with php 7.2.34 (because php 7.4 has some issue with the count() function and this creates many warnings if i check it with debug mode on).

Now, the front page of the shop looks all ok in firefox, edge, chrome.

BUT the back office when i use Firefox is all messed up.

The dashboard looks like the attached image, like there is no styling at all absolutely.

The advanced/performance page looks with some styling but still it is messing up completely how it should be.

In edge or chrome all looks perfectly fine, exactly how they should look.

Any idea?

Yes, since it looks ok the front page, i could always be going to the back office from edge or chrome and do my things, BUT, it should be looking correctly also in firefox.

I cleared cache in firefox, tried to display without style, nothing, problem same.

[texxo]

I dont know how but problem is resolved.

Practically i didnt do something strange, i just modified some values in PHP.ini but i doubt that was the problem.

All good now also on firefox.

[WjaLtd]

Possibly CSS orientated rather than php. 
Perhaps it was sorted after a reload clearing the cache ?

F5 and sometimes CTRL+F5 are useful to force a reload of pages to bring in changes. It can sometimes take a couple of tries.

[texxo]

I think it was combination with clearing cookies etc for the domain from the browser and in plus clearing also the cache file.

Now all looks ok.

[WjaLtd]

Great stuff.
Caches can be quite annoying during development. Perhaps they can be turned off until you go live ?