Hi, I'm new to Twill. I'm using 3.0.0-rc4. I'm trying to get image alt tags to work with the Block Editor. I uploaded an image using the Media manager and set an alt tag. If I upload an image in the Block Editor using a formfield 'medias', I can select an image from the mediamanager. When editing that image, I can see the default alt-text greyed out, but I cannot get thatdefault to show using

$block->imageAltText('image')

- it just shows up empty. If I fill in an alternative alt text in the block editor, that alternative text shows just fine. How can I get it to fall back to the default alt text?