the original symptoms that i reported when i created this thread have continued without break, across all the snappies since [current is 6.2.3105.31]. i have subsequently discovered additional info. all is now summarised in these dot points.
misbehaviour does not occur in firefox
occurs with 100% repeatability in all
linux vivaldi snappies i've tested since thread OP
is not a vivaldi-created bug, coz the identical misbehaviour also occurs in chromium browser
symptom is triggered when trying to stream media from
peertube &
tilvid sites
symptom first [& subsequently] manifested to me when attempting to stream videos from a tilvid site in rss-feed-readers [both vivaldi's native, & also extension rss guard installed in snappie (but
not also feedbro)]
[
new info today] symptom also occurs in chromium & snappie on [at least two] Instances of the Friendica Fediverse web-client, merely whilst attempting to scroll down the timeline. sometimes it occurs almost immediately, whilst other times multiple "page down" actions are possible before the symptom initiates. it seems notable that the timeline typically includes many posts with embedded
peertube &
tilvid videos, so i intuit that it is the same underlying chromium bug that i first noticed with rss feed streaming, which is triggered by these Instances' sites. once the unwanted high network download & upload activity has triggered, it seems never to stop, once again typically lasts 5' to 10' [ie, just like when trying to stream discrete videos in the rss clients] & is accompanied by chromium/vivaldi being very laggy. once the "activity storm" ends & vivaldi becomes more responsive again, the cycle repeats with subsequent Friendica t/l scrolling, to the cumulative point of browser
unviability.
Examples of unwanted spontaneous network activity triggered various times today/tonight, whilst attempting to scroll Friendica timeline in vivaldi.
fc99d0c3-6462-48a1-9cf2-ec66ad02e478-image.png
c8c06f03-9c17-4459-bd79-a084fa68332e-image.png
05f808d1-15c0-4795-9121-5aa5ec683d77-image.png
PS:
This aberrant behaviour was also on Friendica, so clearly Chromium generally, & Vivaldi specifically, has distinct compatibility problems with that site, ie, Friendica Instances, that in effect make it unusable there.