Dawn is the theme every new Shopify store starts with: free, maintained by Shopify, and built as an Online Store 2.0 theme from the ground up. That matters for installing Breadcrumbs Uncomplicated, because Online Store 2.0 themes support app blocks - sections a merchant can drag into place from the Theme Editor, with no code involved at all.
Where the breadcrumb needs to go
A breadcrumb belongs in two places: the Collection template and the Product template. Open Breadcrumbs Uncomplicated in your Shopify admin and the Theme status card lists both, each showing Not added until you place the block.
Adding the block
Click Add to theme next to the Breadcrumbs row for the Collection template. That opens Dawn’s own Theme Editor with the Default Collection template loaded and the breadcrumb block already in place, ready to preview against a real collection page. Move the block up or down in the section list if you want it positioned differently relative to Dawn’s own collection header, then click Save.
Repeat the same step for the Product template: back in the app, click Add to theme next to Breadcrumbs on the Product row, and the Theme Editor opens on the Default Product template with the block ready in the same way.
What happens automatically
Once both blocks are saved, Breadcrumbs Uncomplicated applies no colour or font settings of its own by default, so the trail inherits Dawn’s own link colour, text colour, font and spacing from the shared breadcrumb styling already in your theme, with no additional setup needed - tick Override theme colours on the block if you want to set your own instead. The category structure the breadcrumb follows comes from your Top-level category setting under Settings in the app, and the Refresh Categories button keeps that structure current whenever you change your Shopify Menus.
Summary
On Dawn, installing Breadcrumbs Uncomplicated is two clicks in the Theme status card, one for the Collection template and one for the Product template, each one dropping you straight into the Theme Editor with the block already placed. Nothing in the process touches a code file.