Fills signup forms with a disposable email address and a strong password, then watches that inbox and fills in the verification code when it arrives, without you leaving the page.
Getting started
- Pin the extension. Click the extensions (puzzle-piece) icon in your browser's toolbar and pin BurnerFill, so you can see its badge.
- Turn it on. The extension starts switched off, so nothing happens until you say so. Click its icon: you'll see the off screen. Turn it on there (with the default Blackout style, press and hold the power button until the ring fills).
- Check automatic filling. The pill in the top-right should read ● Auto on. Click it to switch automatic filling off or on. It saves instantly.
- Open any signup page. The extension detects the form, creates a temp inbox and fills the email and password fields for you.
- Submit the form as usual. When the site emails a code, it's filled in automatically.
How a signup works
Detecting a signup page
A page counts as a signup when enough of these point that way: the address contains words like
signup, register or join; there are two password fields; there's an
email field; the form says "Sign up", "Create account" or similar. Login pages ("Forgot password",
"Remember me") are skipped.
What gets filled
- Email: a fresh address from tempmail.lol.
- Password: 16 random characters (letters, digits and symbols, with look-alikes like
0/Oand1/lleft out). - Repeat password: the same password, in confirm fields.
Fields that already have something typed in are left alone.
Watching the inbox
Checking starts the moment the address is created, before you even submit the form:
| When | How often |
|---|---|
| First 25 seconds | Every 5 seconds, since most codes arrive quickly |
| After that | Every 30 seconds |
| After 12 minutes | Stops, and the session is marked Timed out |
Multi-step signups
If the site moves you to another page, say from /register to /register/verify, the
extension keeps using the same inbox as long as you're on the same site and the code hasn't
arrived yet. A new address is only created for a new signup.
The toolbar badge
| Badge | Meaning |
|---|---|
| ● | Temp inbox created, waiting for mail |
| ✓ | Code received |
| ↗ | Verification link received |
| No badge: nothing running on this tab, or it timed out |
Codes & verification links
Verification codes
When an email arrives, the extension looks for a code next to words like "code", "OTP", "PIN" or "verification", or otherwise any 6-digit number. It reads the plain-text version of the email first, which also handles emails that show each digit in its own box.
The code is then:
- filled in on the page, into a single code field or a row of one-digit boxes,
- copied to your clipboard (you can turn this off), so you can paste it where filling didn't reach,
- shown in the popup with a Copy button.
Verification links
Some sites send a "click to confirm your email" link instead of a code. When one arrives, the popup shows an Open verification link button, with the site's address on it so you can see where it goes. You can also have these links open automatically in a new tab (see Settings).
Finding a link doesn't stop the inbox check. If the site sends a code afterwards, it's still picked up.
Manual controls
Automatic detection doesn't catch every site. These always work:
Generate a new email & password
Press Alt+Shift+E on the page, or click Generate new email & password in the popup. You get a brand-new address and password, filled into the page (replacing whatever was there), and the new inbox is watched. The old address is abandoned.
To use a different key, change the shortcut. If another extension already uses Alt+Shift+E, the browser leaves ours unset, and the popup then shows not set.
Right-click to fill
Right-click any text field and choose BurnerFill, then:
- Fill temp email: creates an inbox first if this tab doesn't have one,
- Fill password: the password that goes with that email,
- Fill OTP code: once the code has arrived.
Fields inside embedded frames (for example some sign-in boxes provided by another company) can't be filled this way.
Check now
In the popup, Check now checks the inbox straight away. It also restarts checking if it stopped or timed out.
The popup
Click the extension's icon. The ? button in the top-right opens this guide.
Power button
The ⏻ button next to the Auto pill switches the whole extension off: nothing is detected or filled, the right-click menu disappears, the shortcut does nothing, and inbox checks pause. The toolbar badge shows off. The 12-minute limit keeps running, and checks pick up where they left off when you switch back on.
While it's off, the popup shows an off screen with the control to turn it back on. Choose its style on the Power tab: Blackout (press and hold), Wall switch (flip it) or Shutter (one press).
Session
Everything about the signup on the current tab: its status, the email and password (with Copy buttons), the code once it arrives, and the Inbox, which lists every email received, newest first. Click an email to read it.
The status pill reads Waiting for OTP, Verified, Timed out or Not checking. The line underneath tells you what the last inbox check found. See Troubleshooting for what each one means.
Settings
The options described in Settings.
History
Every account created, newest first, with its password and status (pending, verified or timeout). Export CSV saves them as a spreadsheet (address, password, website, date, status); Clear deletes the list.
Settings
| Setting | Default | What it does |
|---|---|---|
| ● Auto on pill | On | Creates an inbox and fills the form automatically on signup pages. When it's off, use the shortcut, the Generate button or right-click instead. |
| Fill email | On | Puts the temp address into email fields. |
| Fill password | On | Puts the generated password into password fields. |
| Fill repeat password | On | Also fills "confirm password" fields. |
| Auto-submit after OTP | Off | Submits the form once the code is filled in. Leave it off on pages with several buttons near the code field, because it may press the wrong one. |
| Open verification links automatically | Off | Opens an emailed confirmation link in a new tab as soon as it arrives. |
| Copy OTP to clipboard | On | Copies each code as it arrives. This replaces whatever was on your clipboard. |
| API token | Empty | Optional tempmail.lol API key. Leave it empty to use the free service; the label shows which one is in use. |
Troubleshooting
The code never arrives
Open the popup on that tab and read the line under the password:
| It says | What's going on | Try |
|---|---|---|
Checked 12s ago · 0 emails and it stays at 0 |
Checking works, but nothing has arrived. Some sites refuse or quietly drop mail to temporary addresses. | Wait a minute, use the site's "resend code" link, or generate a new address. |
| An email in the Inbox, but no code tag | Mail arrived, but no code was recognised in it. | Open the email in the Inbox and copy the code yourself. |
Last check failed: … |
The request to tempmail.lol failed; the text says why. A 429 means too many checks, and it recovers by itself. |
Check your internet connection, then press Check now. |
Inbox is not being checked. |
Checking stopped. | Press Check now to restart it. |
Stopped after 12 min with no code. |
The 12-minute limit was reached. | Press Check now to look again, or start over with a new address. |
Also make sure the address the site says it sent the code to matches the one in the popup. If you generated a new address after submitting the form, the code went to the old one.
The form wasn't filled
- Reload the page. It may have been open before the extension was installed or updated.
- Make sure the extension isn't switched off: the badge would say off and the popup would show the off screen.
- Check the ● Auto on pill is on, and that Fill email / Fill password are on.
- Use right-click → Fill temp email, or press Alt+Shift+E.
The site says the email isn't allowed
Some sites block temporary email services. Press Alt+Shift+E to try a different address. If the site blocks them all, it can't be used with temp mail.
The shortcut does nothing
Another extension probably uses the same keys. Open the shortcuts page and pick another combination for BurnerFill.
Sending a debug log
If you report a problem, a debug log shows exactly what happened:
- Open the popup and Shift + click the orange B logo. A hidden Debug tab appears.
- Click Clear, then repeat the signup that went wrong.
- Back in the Debug tab, click Copy log and paste it into your report.
The log only records signup and code pages, and keeps the last 400 lines. It contains the temp addresses and email previews, so share it only with someone you trust.
Privacy & data
- Everything stays on this computer. Sessions, history and the debug log are kept in the browser's local storage for this extension. Nothing is synced or uploaded.
- The only outside service is tempmail.lol, which creates the addresses and holds the incoming mail. Like any public temp-mail service, it isn't private, so don't expect confidentiality.
- Passwords are saved in plain text in History, so you can look them up and export them. Anyone using this browser profile can see them. Use Clear in History to delete them.
- The extension reads pages to find forms. It runs on every site so it can spot signup forms, but it only acts on signup and code pages, and it never sends page content anywhere.