[Bug]: .webp cannot be used on macro buttons using lib URI format

[Pmofmalasia]

Describe the Bug

Attempting to use .webp files on macro buttons via tags displays only a broken link when using the addon lib:// URI method. Note, .webp works using the assetID, and other file formats work with the addon lib:// URI.

See discord messages for further context:
https://discord.com/channels/296230822262865920/1279935085583401041/1281996396240572449
https://discord.com/channels/296230822262865920/905157521193455676/1282001901575082088

To Reproduce

Make an addon, add a .webp image to it
Try and set any macro label to show that image using the lib:// URI.
See broken link.

Expected Behaviour

.webp images being displayed.

Screenshots

No response

MapTool Info

1.15.0

Desktop

Windows 10

Additional Context

No response