Performance and accessibility
Tesserae ships no JavaScript libraries and checks every colour combination for contrast. A few habits keep it fast and accessible.
Images and video
Upload images at least 2000 pixels on the long side; the theme serves each visitor the right size. Keep the first section light: one image rather than a video gives the fastest first paint. Use Mobile image for a portrait crop. YouTube and Vimeo embeds load only when the visitor presses play.
Apps
Every app adds scripts to every page, so app scripts are usually the largest cost. Remove apps you stop using and clear their leftover code from Custom Liquid sections.
Accessibility
Tesserae includes a skip link, keyboard-operable menus, drawers, carousels and dialogs, visible focus styles and labelled icon buttons. Give every image meaningful alt text, use one H1 per page, fill the Slideshow and Video description fields, and check any custom text colour against its background.
Without JavaScript
Forms still post, filters submit as ordinary links, menus open as plain lists and the cart page updates on submit, so the store stays usable if a script is blocked.