Since updating, the system on my MacBook Air takes around 120 seconds to load. It used to take around 30 seconds with 10.14.0. I've looked at Login Items for anything that might be causing problems, deleted caches, run OnyX, but can't seem to speed things up.
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.
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