In the admin there are three options for debugging your theme layout:
- Enabled Template Path Hints for Storefront
- Enabled Template Path
- Hints for Admin Add Block Names to Hints
When at least the first one is enabled, you get red rectangles highlighting where a template file starts and ends.
These correspond to all places a block class is mentioned in the layout XML file. If the 3rd option is selected you also see the name of the block class.
Is it possible to output the container name(s) wrapping the blocks?