Search engines like alt text on images, but the editor dialog for adding images doesn't seem to allow it. When I try putting them in manually it breaks the image insertion.
Is there a way to modify this?
It does not support the ALT tag at this time. The blog formatting engine really needs an overhaul and this should be part of that. If you want to try to fix it yourself you can do so in scripts/sb_formatting.php, in the replace_img_tag() function.
I've re-written image handling for my blog as I wanted to use highslide.js to better match the non-blog pages on my site. As part of that rewrite I changed the format of image tags to look like:
* Rewrite to include [/img] where the text between the two tags
* is treated as the image caption.
* The [img] tag has an number of optional attributes -
* width - width of image in pixels
* height - height of image in pixels
* popup - (true/false)
* float - (left/right)
* [img=http://xxx width=xxx height=xxx popup=true float=left]caption[/img]
In my changes the
sets the title. It would be easy to either add an alt=xxx or make the caption also set the alt.