Upgraded FP2 from 2018.04.x (last one with Android6) to 2018.09.2 (Android 7.1.2).
After a day or so, I first noticed this situation. Waking up the FP2, having a lock screen with PIN. Already seeing in the locked state, that the wifi is disconnected. Extending (swiping down) the notification area, also fully extending it downwards with more symbols, the wifi symbol sits there greye with a question mark.
The phone comes back from sleeping, with plenty of battery left (FPOS 2018.09.2 is actually quite a lot better with this Android7 than Android6 state was before, so thank you already for this improvement). The sleeping time was maybe a few minutes or also a longer time. Doesnt seem to matter to this situation. But I have little statistical relevance as this happened to me the sencond time already with this FP2 as I am writing this thread now.
When unlocking the FP2, going into wifi details, it shows, no wifi networks available. Being close to wifi networks though that I have configured and pre-defined. No matter if WPA2 protected wifis or unprotected wifis. It finds, displays and uses none, even though they are available and present, e.g. with other devices, a laptop or other Android based tablets etc.
I think I pretty close to never or very very rarely had this situation on the Android6 levels of FP2.
When I completely disable the Wifi, and re-enable it back, it then finds quickly the wpa2 protected wifis in the vicinity, and then a little bit later shows the unproteced wifis too. Eventually it connects to defined wifis and it uses them, acquires internet connection and everysthing is back to normal and fine.
My usage of FP2 is the following: I dont use this one as a phone, but rather as a tablet, always on airplane mode, but wifi mostly being left turned on. No sims, no nothing fancy. Simple apps from Android/Google play store.
Any clues? Bug? Needing to report? Anyone else reproing or experiencing these problems? Thanks.