... I too had to go into Advanced Settings and flip flop to off and back on. A pain in the backside.
If you can possibly update to Android 12 (don't know how old you phone is to be able to receive updates) or even 13 if possible.
Avast does not notify that Webshield is off, only when I seek to do a scan. I will just have to keep checking.
I don't think I will get further android version updates.
Well you probably know my opinion on on-demand scans and a resident antivirus (much depreciated), so I rarely ever do one. If you don't do one, Avast reminds you to do one if you haven't done one after 7 days. As and when I do one, nothing has been found, shock horror, so generally I ignore these (each to their own).
Periodically I also get a notification 'Avast has done a scan, see what we have found', now this is going to be like what the Smart Scan in the Windows version promotion of other paid Avast services. So I generally ignore that too.
I have just run a scan (and I didn't get a notification that the Web Shield was off), first it told me I hadn't run a scan for 268 days (shock horror). Scan complete and nothing found, but 2 Advanced issues found, enable scam protection and no sensitive apps locked. That produces two options RESOLVE ALL and SKIP FOR NOW, I chose Skip For Now.
My results 432 apps scanned (Have I really got 432 apps I hate default apps) no new threats found, 11 Security settings checked, no new vulnerability settings found. 2 New Files scanned, No New Threats found. Here is the catch 2 Advanced Issues Checked, Upgrade to Premium for additional protection. Essentially this is what I would have expected in a Resident Free Antivirus, nothing found and a promotion of the Premium version.
So for 268 days nothing found other than promoting the Premium version.