MyShare browser extension: when to use it and how
Only the sharer installs the MyShare extension. Visitors need no extension or MyShare account. Use it for independent visitor cookie sign-in, local sharing without webpage CORS setup, or to close the owner tab after connecting. Keep the computer, browser and any local service online.
Product facts checked 2026-09-17 · Official MyShare guide
Do I need the extension?
It is optional. Select self-contained HTML files directly on the website, or use browser sharing when the local server has the required CORS settings and you can keep the owner tab open. Both modes use the same free limits and paid plans.
| Need | Browser mode | Extension mode |
|---|---|---|
| HTML/HTM file or website folder | Only selected files; folders need index.html/index.htm at the root. Select again after edits | |
| Local website, LAN or HTTP API | Exact MyShare Origin and required preflight headers in server CORS; browser local-access permission | Approve specific addresses in the toolbar popup; webpage CORS setup is unnecessary for the extension |
| Visitor Cookie/HttpOnly sign-in | Requires the loopback-only Node project adapter | Isolated visitor credentials for approved loopback/LAN targets |
| Close the owner tab | Sharing stops | Continues after connecting; keep the browser and computer running |
| Local WebSocket / hot reload | Lightweight HMR in ordinary mode; unavailable with the adapter | Unavailable; refresh the visitor preview after project edits |
Use it in three steps
- Open the installation panel and choose your browser. Return to MyShare after installing or loading the package. It detects the extension automatically; refresh if needed on first use.
- Enter a local or private IPv4 service you are authorized to share, or select HTML files. Complete verification and the first-use sharing agreement, then approve the exact addresses in the toolbar popup.
- Wait for the connection, then send the link with its temporary passcode. Visitors sign in to your project with their own account. Stop the share from the website or extension toolbar when finished.
Why these permissions?
Local host permission reads explicitly approved services: one main target and up to two additional origins, fixed for each share. No port scanning. Storage retains share-control state; background capability maintains confirmed connections; request permissions forward each visitor’s isolated cookies. Your browser’s existing sign-in is not passed to visitors.
HTML comes only from the file picker; this does not grant arbitrary filesystem access. Content and necessary request data pass through the Cloudflare gateway to visitors. See the privacy notice for feedback and replay consent and retention.
Browsers and installation channels
The Chromium package targets desktop Chrome 127+; Edge and Brave use the same package. Firefox 140+ uses a separate package; temporary installations need reloading after a restart. Choose an available store or manual download in the installation panel and follow the steps for your browser.
Before sharing
Sleep, quitting the browser, reloading or disabling the extension interrupts sharing. HTML files may need selecting again. The extension does not provide permanent hosting, OAuth, arbitrary TCP/UDP or access to unapproved origins. HTTPS still needs trusted certificates and permitted network access; sign-in redirects must remain within approved services.
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