To compare between two machines, it was easiest to explain the issue through a video: https://youtu.be/4DEfq5Gcpas
I neglected to mention in the video: It seems only browser performance is affected. There aren’t performance issues in the main Anki window or when reviewing cards, as far as I can tell
Another detail is that the performance drop seems to kick in suddenly, when the amount of cards you flip through per unit time exceeds a certain amount. Under that speed, performance is as it should be
The issue extends to applying search/filter parameters in the browser as well (increased loading time)
If you are wondering what the mess is on the right-hand side of the monitor on the windows 8.1 machine, I’m learning to read Wingdings (switching over one Unicode character per day to ease into it)
Thank you for the comprehensive report! Changing the sort field to a field that doesn’t have a lot of text as addons_zz has suggested may help. You could also try resizing the browser window on the slow machine - it takes a certain amount of time to render each row, so the more rows you have visible at a time, the slower it will be.
It’s also possible that the toolkit is not rendering text in an efficient way - if that’s the case, switching to an alternate version or the latest alpha (which both uses different toolkit versions) may also help.
(through 4) Unfortunately trying other Anki versions is not an option. This is due to a suite of addons that I use (Mass Immersion Approach) which only add support for new Anki versions in 6-month intervals
You could also try resizing the browser window on the slow machine - it takes a certain amount of time to render each row, so the more rows you have visible at a time, the slower it will be.
Reducing the number of visible rows definitely improved performance. This lead me to experiment with which columns were visible as well, and it seems by far the biggest performance culprit was the 解答 column (it prints the whole backside of the card)
Performance increases and decreases immediately depending on if the 解答 column is in view. Performance does not depend on how much of the column is shown (whether it’s a single pixel or almost the whole browser, the performance loss is the same). I tried adding the 質問 column as well (prints the front side of the card) and it had a similar effect
Other columns, such as the sort field, are having an affect on performance as well but it is negligible compared to columns like 解答 or 質問
Simply keeping those columns out of view when I don’t need them gets performance to a place I’m quite satisfied with! Though, this doesn’t explain the mystery of why there wasn’t such an effect before the Windows / Anki reinstall
I might have found a clue. I think the text rendering has changed for some reason. I found a screenshot I took with my previous install. Compare it to a screenshot of the same window from the new install (I changed back the language and theme to match) and you can see the text rendering is different now
The old screenshot is pre 2.1.22, judging from the available options. But I can confidently recall that the text rendered the same as in this old screenshot, even on 2.1.22, until just now when I reinstalled Windows and Anki