You're a star! I don't know why disabling content blockers would have an effect on an internal router, but it did. And, it was only a problem since the update. It's Opera's own blocker, rather than an extension.

Anyway, thanks, all fixed now. Cheers.


iMac (19,1, 3.1 GHz i5, 12.7.4, 40 Gb RAM); MacBook Air (1.8 Ghz, 8 Gb RAM, 10.14.6, 256 Gb SSD) Vodafone router and Devolo Wi-Fi Extender, Canon TS8351 printer/scanner.