Bugzilla

(In reply to Daniel Holbert [:dholbert] from comment #3)
> Details below, but briefly: I think my Firefox session is in X11 mode, and MOZ_USE_XINPUT2 doesn't change anything AFAICT; and if I opt in to using Firefox in wayland mode, then I get a new and different behavior (scrolling slightly less far but still pretty far).

One followup point on this -- my above-quoted text sounded like Wayland would be a slight improvement, but I've found that this bug is way-more-annoying with Wayland enabled (which it is now per bug 1749174), due to a Wayland-specific "kinetic scroll" feature that we seem to have.

With Wayland enabled, it looks like touchpad-scrolling triggers a kinetic after-effect, where the scroll continues gliding even after you release your fingers.  As a result of this bug here (where we're over-estimating the velocity of touchpad scrolls, including with Wayland to a slightly lesser extent), this kinetic glide ends up scrolling extremely far,  with just a gentle brush of my touchpad.

This makes touchpad-scrolling kind of unusable on my machine, unfortunately, unless I'm very careful to leave my fingers on the touchpad to prevent the kinetik-scroll "fling" after-effect.

(In reply to Daniel Holbert [:dholbert] from comment #3)
> Details below, but briefly: I think my Firefox session is in X11 mode, and MOZ_USE_XINPUT2 doesn't change anything AFAICT; and if I opt in to using Firefox in wayland mode, then I get a new and different behavior (scrolling slightly less far but still pretty far).

One followup point on this -- my above-quoted text sounded like Wayland would be a slight improvement, but I've found that this bug is way-more-annoying with Wayland enabled (which it is now per bug 1749174), due to a Wayland-specific "kinetic scroll" feature that we seem to have.

With Wayland enabled, it looks like touchpad-scrolling triggers a kinetic after-effect, where the scroll continues gliding even after you release your fingers.  As a result of this bug here (where we're over-estimating the velocity of touchpad scrolls, including with Wayland to a slightly lesser extent), this kinetic glide ends up scrolling extremely far,  with just a gentle brush of my touchpad.

This makes touchpad-scrolling kind of unusable on my machine, unfortunately, unless I'm very careful to leave my fingers on the touchpad to prevent the kinetic-scroll "fling" after-effect.

(In reply to Daniel Holbert [:dholbert] from comment #3)
> [...] if I opt in to using Firefox in wayland mode, then I get a new and different behavior (scrolling slightly less far but still pretty far).

One followup point on this -- my above-quoted text sounded like Wayland would be a slight improvement, but I've found that this bug is way-more-annoying with Wayland enabled (which it is now per bug 1749174), due to a Wayland-specific "kinetic scroll" feature that we seem to have.

With Wayland enabled, it looks like touchpad-scrolling triggers a kinetic after-effect, where the scroll continues gliding even after you release your fingers.  As a result of this bug here (where we're over-estimating the velocity of touchpad scrolls, including with Wayland to a slightly lesser extent), this kinetic glide ends up scrolling extremely far,  with just a gentle brush of my touchpad.

This makes touchpad-scrolling kind of unusable on my machine, unfortunately, unless I'm very careful to leave my fingers on the touchpad to prevent the kinetic-scroll "fling" after-effect.

(In reply to Daniel Holbert [:dholbert] from comment #3)
> [...] if I opt in to using Firefox in wayland mode, then I get a new and different behavior (scrolling slightly less far but still pretty far).

One followup point on this -- my above-quoted text sounded like Wayland would be a slight improvement, but I've found that this bug is way-more-annoying with Wayland enabled (and it is now enabled by default in Nightly/early-beta, per bug 1749174), due to a Wayland-specific "kinetic scroll" feature that we seem to have.

With Wayland enabled, it looks like touchpad-scrolling triggers a kinetic after-effect, where the scroll continues gliding even after you release your fingers.  As a result of this bug here (where we're over-estimating the velocity of touchpad scrolls, including with Wayland to a slightly lesser extent), this kinetic glide ends up scrolling extremely far,  with just a gentle brush of my touchpad.

This makes touchpad-scrolling kind of unusable on my machine, unfortunately, unless I'm very careful to leave my fingers on the touchpad to prevent the kinetic-scroll "fling" after-effect.