Problem editing large menus - 200 odd items 403 error
This all sounds like something's wrong with your server, but also i'm not sure what you mean by non complying hardware?
If you could file a bug report here please https://dev.tiki.org/File-a-bug and set up an example "show instance" on tiki 24.x then maybe i can export that and work out what the problem is?
I'll try it all in Edge when i next get a chance, but its all works fine in Chrome and similar browsers for me...