Output spacing is uneven on Pixel 4XL, producing "ripple" as LW66 output scrolls

[jamesyoungman]

Describe the bug
The gap between consecutive lines of the Lincoln Writer 66 output on a Pixel 4 XL is slightly smaller than the gap between the last line of history and the "current" line. This produces a mild rippling effect as output lines are completed.

To Reproduce

1. Visit https://tx-2.github.io/demo/ on a mobile device.
2. Follow the getting-started instructions to load and run the "hello" tape.
3. Observe the "ripple" effect as the output is generated.

Expected behavior
Output scrolls up with no discernible difference between the final two lines and any other pair or adjacent lines.

Screenshots
Not at this time.

Platform and version information:
Pixel 4XL, Android version 12.
Reproduced with version 2d5f016

Additional context
This does not occur on the desktop Chromium instance I use for development. I don't know whether this affects other mobile devices.