This site uses a ton of tracking and ad scripts. Do you use any add-ons that could be blocking content in the page? Or Firefox's Tracking Protection feature because it's a private tab?

For Tracking Protection, check the address bar for a shield icon. You can tap that to open the site information panel and tap "Disable Protection" at the bottom to reload the page without those scripts blocked. Screenshot example attached.

Thank you for responding - much appreciated.

I have no Add-ons and don't use the Tracking Protection. However, on a moment of inspiration I stopped the DNS66 app and realized that it was to blame.

Cheers!

Oh, that's interesting. Maybe it has a filtering component.

DNS66 creates a VPN that intercepts DNS traffic and forward queries that are not blacklisted, so - yes - it's all about filtering. Inadvertently, it must remove some code that disables next/previous slide in the Digital Trends' (DT) slide shows.

However, using my Galaxy Tab S3 Samsung browser (un-installable bloatware) there is no problem changing slides with the DNS66 on, so the issue is FF related. Earlier I used Chromium without any problems either.

Given its likely limited occurrence (other web sites slideshows so far work for me with FF + DNS66) we may end up just speculating why FF in particular have issues with DT's site.

Anyway, have a good one and keep up the good work!