Comment 8 for bug 2044033

By examining chrome://version/?show-variations-cmd on a Chrome instance that was known to be recently impacted by this, I was able to identify a likely variation / field trial.

Launching Chrome with the following flags (and with "Preload pages" not otherwise disabled) greatly helps in the effort to reproduce. Tested on Windows 10 with Chrome 119.0.6045.160 against Evergreen 3.11.

"C:\Program Files\Google\Chrome\Application\chrome.exe" --force-fieldtrials="*Prerender2BookmarkBarTrigger/Default/" --force-fieldtrial-params="Prerender2BookmarkBarTrigger.BothMouseDownAndMouseHover_20231102:prerender_bookmarkbar_on_mouse_hover_trigger/true/prerender_bookmarkbar_on_mouse_pressed_trigger/true/prerender_start_delay_on_mouse_hover_ms/300" --enable-features="BookmarkTriggerForPrerender2<Prerender2BookmarkBarTrigger"

Further testing shows that only the --enable-features part may be required to reproduce with 119.0.6045.160:

"C:\Program Files\Google\Chrome\Application\chrome.exe" --enable-features="BookmarkTriggerForPrerender2<Prerender2BookmarkBarTrigger"

With this command line, I am able to reproduce the problem (or possibly a slight variation of it) on Chrome 118.0.5993.144 (extended stable).

So far, I have been unable to reproduce the issue with Chrome 120 (beta) or Chrome 121 (dev). I don't know if I should find that encouraging or not. Absent a clear bug report and test case to confirm, we should probably not assume that the issue is a bug that has already been fixed. :-(