Currently the the “#has” handlebars helper (in post/page templates) matches tags by name, not by slug.
{{#has tag="photo, video, audio"}}
This works great until you have built specific tag checking into custom theme post or page templates, then later decide to rename the tag.
Because tags names and slugs can be changed independently, and because tag slugs are used to generate CSS selectors, tag slugs can generally be expected to be more stable than their names.
Therefore, I propose “tag-slugs” (or a more apropriate equivalent) be added as a matcher to the #has helper, to allow themes to be coded against the slugs.