I have a Sony Xperia XZ1 Compact (G8441), less than 1 year old, Android 8.0.0, etc.
Under Wi-Fi preferences > Advanced, I have set "Wi-Fi on during sleep" to "when plugged in only." This is what I want, to preserve battery.
Until the latest system update a few weeks ago, this was fine: WiFi would disconnect when asleep, but every 20 minutes or so the phone would automatically re-connect to check for new e-mail, and when I woke the phone, after 5 seceonds it would re-connect to wifi.
NOW, the phone does NOT automatically re-connect to WiFi, and when I go to Wifi Settings to turn it on manually, the phone freezes before I can even turn WiFi to "on". Sometimes it says "Settings has stopped responding"; sometimes it just freezes, and I can't even re-start: I have to do a hard re-start by pressing power+volume down x 6 seconds. Restarting my phone just to connect to WiFi every time it wakes from sleep is a very slow process compared to the 5-10 seconds previously!
Does anyone else know about this problem? Any work-arounds (other than having WiFi remain connect always, with significant costs in battery life)?
ps: it seems like this problem happens at many (but not all) of my regular wifi locations; at the affected locations it happens *every* time my phone wakes; and this *never* happened at those locations before this month.
