GPU usage surge on custom, small tiling tooltips

Issue

As of version 25w18a to present 1.21.7: custom tooltips that use tiny and repeating patterns of pixels (less than 2x2) now lag when rendering larger tooltips.
This issue was not present in versions 1.21.2 to 1.21.5.

Steps to Reproduce

Load into any world with commands and use the provided resource pack (tooltip_issue.zip).

Activate advanced tooltips with F3+H for a larger tooltip size, then run this give command:

/give @p minecraft:waxed_weathered_cut_copper_stairs[minecraft:tooltip_style="custom_tooltips:solid"]

Finally, hover over the item in any container.

Optionally, activate the FPS Chart with F3+2 and then hover over the item.

Observed Behavior

The game uses a lot more resources to render the tooltip compared to previous versions, and visibly lags the game.

Expected Behavior

The game should render the tooltip as it has in previous versions without lag.

Notes

Unexpectedly, transparency of the tooltip image does not affect performance.