LinkedIn from your browser: the free extension
New in October 2026. Runs while your browser is open and you're signed in to LinkedIn — upgrade to a Cloud seat to run 24/7.
LinkedIn from your browser is WarmySender's free way to run LinkedIn-only campaigns inside your own browser, on your own connection, while that browser is open and you are signed in to LinkedIn. It sends the connection requests and messages your campaign has scheduled, and it syncs your inbox. It uses the same safe daily limits and warm-up as every account. One campaign uses one account.
It is included with your plan:
- Pro: 1 account
- Enterprise: 4 accounts
- Ultimate: 10 accounts
- A trial includes the allowance of the plan you are trying. A Pro trial includes 1 account, an Enterprise trial includes 4, and an Ultimate trial includes 10.
- AppSumo lifetime plans: not included. That extension is not part of the AppSumo deal. LinkedIn on an AppSumo plan is the Cloud seat add-on.
A free plan with no trial includes none.
Where it runs: Chrome, Edge, Brave, Arc, Opera and Vivaldi. Firefox and Safari aren't supported yet. To run LinkedIn without one of these browsers, use a Cloud seat. See /documentation/linkedin-browser-or-cloud-seat.
Install it from our page at /linkedin-extension. There are five steps:
- Download the zip and unzip it somewhere you will keep, for example Documents. You get a folder called WarmySender-LinkedIn-Extension. The browser loads the extension from this folder, so do not delete or move it afterwards.
- Open your browser's extensions page and turn on Developer mode. Where both are, browser by browser, is in the list below.
- Click Load unpacked and choose the WarmySender-LinkedIn-Extension folder (the one with manifest.json directly inside). The extension appears in the list straight away.
- Sign in to LinkedIn in a tab, using the account you want campaigns to run from, and keep that tab open while campaigns run.
- In WarmySender, go to LinkedIn → Accounts → Connect → Run from your browser. The extension pairs itself the moment the connect dialog is on screen. There is nothing to type. The dialog ticks off each step on its own (Install, Sign in to LinkedIn, Confirm) and shows the LinkedIn name and photo it found. Check it is you, then click This is me — start.
Your browser, step by step:
Chrome
• Extensions page: Paste chrome://extensions into the address bar and press Enter.
• Developer mode: The switch is in the top-right corner of the Extensions page.
• Button to click: Load unpacked
• After an update: press the circular reload arrow on the WarmySender card
• Start-up notice: At start-up the browser may ask whether to "Disable developer mode extensions". Choose Cancel. Disable would switch the WarmySender extension off.
Edge
• Extensions page: Paste edge://extensions into the address bar and press Enter, or open the ⋯ menu → Extensions → Manage extensions.
• Developer mode: The switch is on the left-hand side of the Extensions page.
• Button to click: Load unpacked
• After an update: press the Reload link on the WarmySender card
• Start-up notice: Edge shows a notice about extensions in developer mode, and Microsoft doesn't allow that notice to be switched off. You can ignore it: the extension keeps working as long as you don't choose to turn developer-mode extensions off.
Brave
• Extensions page: Paste brave://extensions into the address bar and press Enter.
• Developer mode: The switch is in the top-right corner of the Extensions page.
• Button to click: Load unpacked
• After an update: press the circular reload arrow on the WarmySender card
• Start-up notice: At start-up the browser may ask whether to "Disable developer mode extensions". Choose Cancel. Disable would switch the WarmySender extension off.
Arc
• Extensions page: Press ⌘T (Mac) or Ctrl+T (Windows), type Manage Extensions and press Enter.
• Developer mode: The switch is in the top-right corner of the Extensions page.
• Button to click: Load unpacked
• After an update: press the circular reload arrow on the WarmySender card
• Start-up notice: At start-up the browser may ask whether to "Disable developer mode extensions". Choose Cancel. Disable would switch the WarmySender extension off.
• Note: Arc's maker is retiring Arc on December 22, 2026. After that date, install the extension in another browser on this list.
Opera
• Extensions page: Paste opera:extensions into the address bar and press Enter, or press Ctrl+Shift+E (⌘⇧E on Mac).
• Developer mode: Look for it by name on the Extensions page.
• Button to click: Load unpacked (some versions say Load unpacked extension)
• After an update: press the reload button on the WarmySender card
• Start-up notice: At start-up the browser may ask whether to "Disable developer mode extensions". Choose Cancel. Disable would switch the WarmySender extension off.
Vivaldi
• Extensions page: Paste vivaldi://extensions into the address bar and press Enter, or press Ctrl+Shift+E (⌃⌘E on Mac).
• Developer mode: The switch is in the top-right corner of the Extensions page.
• Button to click: Load unpacked
• After an update: press the circular reload arrow on the WarmySender card
• Start-up notice: At start-up the browser may ask whether to "Disable developer mode extensions". Choose Cancel. Disable would switch the WarmySender extension off.
What runs, and what waits:
- While the browser is open and you are signed in to LinkedIn, scheduled connection requests, messages and inbox sync run, one at a time, inside the normal daily limits and warm-up.
- If you close the browser, quit it, or you are signed out of LinkedIn, the campaign waits. Nothing is lost, nobody is skipped, and the campaign continues from the next person when the browser is open and you are signed in again.
To keep it running smoothly:
- One browser profile per LinkedIn account. Each browser profile runs one LinkedIn account. To run a second account, add a second profile, install the extension there and sign in to the other account in that profile.
- Your own LinkedIn activity counts too. LinkedIn counts the invites and messages you send by hand together with the ones your campaign sends, against the same daily limits. On a day you send a lot yourself, give the campaign a lighter day.
- Do not sign out of LinkedIn in that browser. Signing out pauses the account. Sign in again and it picks up where it stopped.
- If the browser is closed, the campaign simply waits. Nothing is skipped and nothing is sent twice.
Example: you are on Pro, so you have 1 free account. You install the extension, pair it, and start a LinkedIn-only campaign of connection requests. While the browser is open and you are signed in, invites go out inside the daily limit. You close the laptop at the end of the day. The campaign waits overnight. In the morning you open the browser and sign in to LinkedIn, and it continues with the next person.
About the developer-mode notice: because the extension is installed from a folder rather than a store, your browser reminds you about it. The list above says what each browser shows and what to click. In short, keep the extension on and never choose the option that turns developer-mode extensions off.
Update: folder-installed extensions do not update themselves. When a new version is ready, the install page and the extension tell you.
1) Download the new zip and unzip it.
2) Replace everything inside your WarmySender-LinkedIn-Extension folder with the new files.
3) On your browser's extensions page, press reload on the WarmySender card (a circular arrow, or a Reload link in Edge).
Remove:
1) On your browser's extensions page, click Remove on the WarmySender card.
2) In WarmySender, open LinkedIn → Accounts, click ⋮ on that account and choose Remove account.
Then you can delete the folder.
Troubleshooting:
- The extension's card shows errors: download the zip again, replace the folder's contents, and press reload on the card.
- "Extension detected" never ticks on the install page: reload that WarmySender tab after loading the extension.
- The LinkedIn tab must be open and signed in. Campaigns wait while LinkedIn is signed out.
- One browser profile per LinkedIn account.
- If the Developer mode switch is greyed out or Load unpacked is missing, your browser is managed by a workplace or school and folder-installed extensions are blocked. Use a personal browser profile, or a Cloud seat.
Limits and safety: the extension only performs actions your campaign has already scheduled. It does not raise a daily limit, and an AI agent cannot raise one either — WarmySender's scheduler paces every connection request and message. Connecting and disconnecting the account stays in the app. One account per campaign. InMail, liking or commenting on a post, skill endorsements, multichannel sequences (email plus LinkedIn) and multi-account rotation are not part of the free extension; they run on a Cloud seat. Those need a Cloud seat. See /documentation/linkedin-browser-or-cloud-seat.
Frequently asked questions:
Does closing the browser delete my campaign?
No. The campaign waits. Open the browser, sign in to LinkedIn, and it carries on. Prospects stay enrolled at the step they had reached.
Do I type a pairing code?
No. Open LinkedIn → Accounts → Connect → Run from your browser. The extension pairs itself.
Which browsers work?
Chrome, Edge, Brave, Arc, Opera and Vivaldi. Firefox and Safari aren't supported yet. To run LinkedIn without one of these browsers, use a Cloud seat.
How many accounts do I get?
Pro 1, Enterprise 4, Ultimate 10. A trial uses the allowance of the plan you are trying. AppSumo lifetime plans get none.
Can I run email and LinkedIn in one sequence on the free extension?
No. That is a multichannel sequence, and it needs a Cloud seat. The free extension runs LinkedIn-only campaigns.
Why did a step show "Handed back"?
The extension picked up the step but could not act on it. Usually the LinkedIn tab was closed, you were signed out, or the extension was paused from its toolbar button. Nothing was sent to LinkedIn. The step went back into the queue automatically and runs at the next chance, inside the same daily limits. There is nothing you need to do.
Full install page: /linkedin-extension. Compare the two options: /documentation/linkedin-browser-or-cloud-seat.