I know there are loads of threads and you're working through the issues, but one is new and one has been a problem since the site change.
I'm on Firefox, mobile browser on Android, and desktop - same issues on both.
I'm still seeing 5 blank rows (blue and white striped rows) at the top of 'Active' or any sub-board (e.g. AIBU, Site Stuff). The list of threads begins under the 5 blank rows.
Also - this is new. My "Customise - Settings" here www.mumsnet.com/settings/talk has no changeable settings. I had definitely switched off email notifications for everything last week/sometime after the change, and had changed other settings like the colour of OP/my posts.
Notifications are back on again, and I'm getting tons of emails, and I can't change this.
(I also second, again, the plea to have the OP be collapsed - but expandable - o page 2+ of all threads!)