How to use Line Break Converter.
From install to your first preserved-line-break post — about ninety seconds. This guide walks you through every screen, every toggle, and the small handful of things that can trip you up.
Install the extension
Two paths: the Chrome Web Store (one click) or unpacked from a folder (for self-hosted builds).
From the Chrome Web Store — recommended
Open the listing and click Add to Chrome, then Add extension on the confirmation popup. Chrome will download the extension and you'll see the icon appear in the extensions area next to your address bar.
Unpacked — for the developer build
If you were given a folder (or downloaded the source), you can side-load it directly:
- Open Chrome and go to
chrome://extensions. - Toggle Developer mode in the top-right.
- Click Load unpacked and select the
Line Breakerfolder.
A file picker opens — point it at the folder containing manifest.json.
Pin it to your toolbar
You'll want one-click access to the popup. The pin lives behind the puzzle-piece icon by default.
Click the puzzle-piece icon in the top-right of Chrome to open the extensions menu, find Line Break Converter, and click the pin icon next to it. The extension icon now sits in your toolbar full-time.
The five-step paste flow
The whole reason this thing exists. You write somewhere comfortable, then paste — and Facebook stops eating your formatting.
Write & copy
Compose your post in Notes, Word, ChatGPT — anywhere.
Open FB or IG
Visit a whitelisted site. The icon turns green.
Click the field
Post composer, caption box, or any comment.
Paste
⌘+V on Mac, Ctrl+V on Windows.
The extension hooks the paste event, rewrites empty lines with an invisible non-breaking space (U+00A0) so the platform's autoformatter keeps them, swaps runs of multiple spaces for non-breaking spaces too, and drops the result into the field. You don't click anything else — the transformation happens between V going down and your cursor showing up on the next line.
Without the extension
You don't need a data science team. You need 2 days and the right tools. Sales forecasting on Day 2. Pricing on Day 3. Limited seats. Reply for details.
→ Facebook collapses every blank line into one dense wall of text. Same words, but readers scroll past in a second.
With the extension
You don't need a data science team. You need 2 days and the right tools. Sales forecasting on Day 2. Pricing on Day 3. Limited seats. Reply for details.
→ Same paste, but the blank lines now contain an invisible character — FB preserves them as written.
Popup controls, annotated
Five elements, in order. Click the icon to open the popup any time.
Global on/off switch
The big red button. When off, paste behavior is untouched everywhere, even on whitelisted sites. Use this to A/B test whether the extension is the cause of something weird.
Add a blank line between paragraphs
Enabled by default. Turns single line breaks into the visually airier double-spaced look — the classic FB promo post. Disable it if you write posts that already include their own paragraph spacing.
Whitelisted sites
One domain per line. The extension only fires here. Subdomains are matched automatically — see the next section for examples. Click Save to apply, or Reset to defaults to restore facebook.com and instagram.com.
Manual converter
For sites you don't want to whitelist, or for places where paste interception isn't possible (a desktop app, a friend's Mac, etc.). Paste in, hit the button, and the converted text is on your clipboard.
Active on the current tab
Reads the hostname of the tab you're on and tells you, at a glance, whether the extension will act if you paste right now. Yes in green = good to go.
Adding sites to the whitelist
How the domain matcher actually works — so you know what to type.
Subdomains are matched automatically. You almost always want the bare apex domain (example.com) — that one entry covers every subdomain under it.
Whitelist entry
- facebook.com
What it matches
- www.facebook.com
- m.facebook.com
- business.facebook.com
- web.facebook.com
- facebooklookalike.com (unrelated, not matched)
https://www.linkedin.com/feed/ from your address bar and drop it into the whitelist, the popup normalizes it to linkedin.com automatically before saving.
Using the manual converter
For one-off pastes and sites you'd rather not whitelist.
Open the popup
Click the toolbar icon, scroll to Manual converter.
Paste your text
Into the textarea, exactly as you'd want it formatted.
Convert & copy
The transformed version is now on your clipboard.
Paste anywhere
Threads, LinkedIn, X, a webmail draft — anywhere.
Troubleshooting
If something looks off, this list covers ninety-five percent of it.
I pasted and nothing changed — line breaks still vanished.
Open the popup and check two things: the global toggle is on, and the footer says Active on the current tab: Yes. If you're on a Facebook subdomain that isn't in your whitelist (rare, but it happens), add the apex facebook.com and reload the tab.
Reloading the tab matters: content scripts attach on page load, so any whitelist change needs a refresh to take effect on already-open tabs.
Every paste is being transformed twice.
You probably have both the Web Store version and the unpacked version installed. Open chrome://extensions, find any duplicate, and remove one.
The popup says "Active on the current tab: No" but I'm on facebook.com.
The "Active" check reads the hostname of the tab in the foreground. If you just opened the popup from a different tab (say, your inbox), it'll say No because that other tab isn't whitelisted. Switch to the FB/IG tab first, then open the popup.
Can I use it on LinkedIn / Threads / Bluesky / X?
Yes. Add the domain to the whitelist (linkedin.com, threads.net, bsky.app, x.com) and the same paste behavior applies. The invisible-space trick is platform-agnostic — anywhere that collapses blank lines on paste, it works.
Does it work in the Facebook iOS / Android app?
No. This is a Chrome extension; it lives in the desktop browser. For mobile workflows, use the manual converter: convert text in the popup on desktop, then send the converted text to your phone (via your favorite cross-device clipboard or a self-message). When you paste it on mobile, the invisible characters are still there.
Does it send my text anywhere?
No. Everything happens locally in your browser. There are no network calls, no analytics, no accounts. Settings are stored in Chrome's built-in chrome.storage.sync so they follow your profile across devices, but the content of your pastes never leaves the machine.
Why is there an invisible character in my post?
That's the trick that makes the whole thing work. U+00A0 (a non-breaking space) is a Unicode character the platform treats as real content, so Facebook's autoformatter sees the line as "not empty" and leaves it alone. Visually, it's indistinguishable from a real blank line, and it doesn't affect search or copy-paste from your post.
How do I uninstall?
Right-click the toolbar icon → Remove from Chrome, or go to chrome://extensions and click Remove on the Line Break Converter card. Your saved settings are wiped automatically.