Bug tracking for Astro — session replay, console + HAR (2026)

Astro's pitch is "ship zero JavaScript by default" — but the bugs your team will hit are not in the static HTML, they're at the **island boundaries**. A `<MyButton client:visible />` hydrates only when scrolled into view; a `<MyForm client:load />` hydrates on every page. Picking the wrong directive turns a 0-KB page into a 200-KB page, or a fast page into a janky one.

A useful Astro bug report needs the page route (static, server, hybrid?), the island component name + client directive, and what the user saw before AND after hydration. BugMojo captures both halves — the server-rendered HTML and the client takeover — in the same replay.

This guide covers Astro island hydration gotchas, view transitions bugs (Astro's native router), and the recommended BugMojo capture workflow for Astro teams in 2026.

Framework-specific failure modes engineers actually ship through. Each is hard to spot in a screenshot and obvious in a session replay.

Real Astro bug patterns — the symptom you will see in a report and the fix that actually works.

Island state resets on navigation with view transitions

Symptom: A persistent header with a search input loses its value when navigating between pages.

Fix: Add `transition:persist` on the element AND on the framework wrapper. View transitions only persist marked elements.

Environment variables undefined in client islands

Symptom: `import.meta.env.MY_KEY` is undefined when called from a hydrated island.

Fix: Astro env vars are scoped by prefix — `PUBLIC_*` are exposed to client, everything else is server-only. Rename to `PUBLIC_MY_KEY`.

Markdown component imports work in .md but not in .mdx

Symptom: `import` at the top of an MDX file fails to resolve.

Fix: MDX in Astro requires `@astrojs/mdx` integration AND component imports must be inside the frontmatter, not at the top of the file body.

The honest comparison — where BugMojo wins, and where another tool might serve you better.