Hi,
Please update to the latest version and if the issue persists, provide a support file ID, and we can look into it.
https://support.avast.com/article/Submit-support-file
I see.
Though I simply wanted to know what exactly could cause it, since the log clearly has information which should be familiar to the developers, as I assumed. And I thought I could get at least some pointers about what it could be.
So I could try to solve it myself.

Unless it's just an issue this version of the program is known for (then it's fine).
I can't update the program because I keep reading about every single new version since that one how many new bugs or issues (especially for old systems like my Windows 7 SP1) get introduced to the program. And I don't want to deal with new issues.
I even had to turn off both Emergency update and Overseer in the Task Scheduler a few weeks ago, because it wouldn't stop bothering me reapplying the same exact update (judging by the logs) and the program then showed I had to reboot my PC.
I know it's my own fault (so to speak) to keep using Windows 7, but that's my choice.
If this issue can't be pin-pointed without sending a full report, then I'll have to just live with it and once a weak open a program's window so the memory leak resets itself.
It's just this particular version of Avast
is the most stable one (on my computer) I had for the past 12 months or so, and I don't feel like experimenting again just to be forced to clean remove everything and install this old verison once again, wasting my time...
Besides, I'm sure that all the developers of Avast don't focus on the testing of the new versions of Avast for OS like Windows 7. That's to be expected, considering the OS is considered outdated (even if it has its strong sides and still can be used effectively, depending on the user).
So it's unlikely that Avast will be working better with more updates in the future. It's actually more likely Avast will be working worse for outdated OS, and support them less and less.