Mozilla has officially rolled out Firefox 145, the latest version of its open-source web browser. This new update may not look revolutionary at first glance, but it introduces some genuinely useful quality-of-life improvements, smarter tools for both everyday users and developers, and even a bittersweet farewell to 32-bit Linux builds.

Let’s explore everything new in Firefox 145 — from PDF annotations and tab previews to advanced security headers and multimedia support.

---

🌍 1. A Quick Overview: What Makes Firefox 145 Special?

Before we dive into the detailed breakdown, it’s worth understanding the focus of this release. Firefox 145 isn’t about flashy redesigns — it’s about polishing the browser experience and bringing useful, productivity-oriented updates.

Here’s what Mozilla prioritized this time:

• Improving the way users interact with PDFs.
• Enhancing tab organization through live previews.
• Introducing semantic search to find web history faster.
• Expanding multimedia compatibility for open formats.
• Refining the browser interface for visual consistency.
• Adding new developer and security tools.

Now let’s go step by step and unpack each of these new features in detail.

---

📝 2. PDF Annotation: Add, Edit, and Delete Comments Natively

If you frequently read or review PDFs, this feature will make your day.
Firefox 145 now lets you add, edit, and delete comments directly inside PDF files, without needing any extensions or third-party apps.

When you open a PDF in Firefox, you’ll notice a new comment sidebar that allows you to:

• Highlight text and attach notes.
• Write questions, reminders, or clarifications.
• Manage all your annotations in one clean panel.

This feature is particularly helpful for students reviewing digital textbooks, researchers noting sources, or professionals providing feedback on documents — all within the browser.

Let’s move on to something that affects how you browse multiple pages at once.

---

🗂️ 3. Tab Group Previews: Organize Smarter, Browse Faster

If your browser window often looks like a chaotic collection of 30 open tabs, Firefox 145’s tab group preview feature is a small but welcome addition.

Now, when you hover over a tab group name, a preview panel instantly shows which pages belong to that group — without needing to expand it.

This makes managing large sessions or topic-based browsing (like “Work,” “Shopping,” “Research”) far easier. You can check what’s inside each group at a glance and switch with confidence, rather than opening multiple windows.

---

🔗 4. Copy Link to Highlight: Share Precisely What Matters

Here’s another small but clever enhancement — the Copy Link to Highlight feature.

Let’s say you’re reading a long article and want to share a specific sentence with a friend. With this new feature:

1. Highlight the text.
2. Right-click and choose Copy Link to Highlight.
3. Send the link.

When the recipient opens it in Firefox, that exact portion of text will be automatically highlighted in yellow.

This saves time, keeps context intact, and makes sharing educational or news content far more precise. It’s one of those quiet improvements that you don’t realize you need — until you use it once.

---

🧠 5. Semantic History Search: Find Pages by Meaning, Not Just Words

So far, we’ve looked at surface-level usability upgrades. Now, let’s move into the most innovative — and experimental — feature of this release: Semantic History Search.

Instead of searching your browsing history using exact keywords, Firefox 145 allows you to use natural-language queries.

For instance:

“That Linux article about Varnish caching”
“The guide I read on password managers last week”

Firefox will analyze the context and retrieve the right page — even if you don’t remember the exact title or URL.

What’s more impressive is that this entire process happens locally, ensuring your search data never leaves your device. Mozilla continues to champion privacy, and this feature reinforces that promise.

---

🎨 6. UI Consistency and Visual Refinement

Now let’s talk about aesthetics — something you’ll notice right away even if you’re not a designer.

Firefox 145 makes several subtle UI improvements:

• Horizontal tabs now feature gently rounded corners, matching the design of vertical tabs.
• Buttons, input fields, and the address bar have been refined for a more cohesive, modern look.
• When no extensions are installed, clicking the extensions button now opens a friendly prompt with suggestions from the official Firefox Add-ons Store, helping users discover customization options safely.

These refinements may sound small, but they contribute to a smoother, more unified visual experience across platforms.

---

🧑‍💻 7. Developer and Platform Enhancements

Developers also have plenty to explore in this release. Firefox 145 adds new capabilities under the hood that improve performance, threading, and web security.

Here’s a closer look at the key changes:

• Atomics.waitAsync Proposal Support

This new addition enables non-blocking synchronization between threads for shared memory operations. In plain English — it allows web apps to handle concurrent tasks more efficiently, reducing lag and improving responsiveness in multi-threaded JavaScript environments.

---

• Integrity Policy Header

Firefox now includes initial support for the Integrity Policy Header, which helps enforce Subresource Integrity (SRI) for scripts and assets.

This means websites can define policies that ensure only trusted scripts are loaded, adding another layer of protection against supply-chain attacks and malicious code injection.

So far, we’ve seen features for productivity and privacy — but Firefox 145 also upgrades how we watch and listen online.

---

🎬 8. Better Multimedia and Font Handling

Modern browsers are multimedia hubs, and Firefox continues to strengthen its open-format compatibility.

With version 145, Matroska (.mkv) video files now work smoothly using a wide range of popular codecs:

• AVC
• HEVC
• VP8 / VP9
• AV1
• AAC
• Opus
• Vorbis

This ensures smoother video playback across streaming platforms and self-hosted media without needing proprietary plugins.

Additionally, support for the text-autospace CSS property improves spacing between characters when mixing scripts (like Latin and East Asian text), enhancing typography and readability on multilingual websites.

---

🧱 9. End of an Era: No More 32-bit Linux Builds

Every release brings progress — but sometimes, progress also means saying goodbye.

Firefox 145 officially ends support for 32-bit Linux systems. Mozilla now recommends that all Linux users upgrade to 64-bit builds for continued updates, performance improvements, and security fixes.

While this may inconvenience users on older machines, the decision reflects modern computing realities — nearly all mainstream Linux distributions and processors today are 64-bit capable. Dropping 32-bit allows Mozilla’s team to focus development resources on performance and stability improvements that benefit the majority.

---

🚀 10. Updating to Firefox 145

If you’re eager to try these features right now, you don’t have to wait long.

Here’s how to get the new version:

• Windows and macOS users:
  Firefox will automatically update in the next few days. You can also manually trigger it from
  Menu → Help → About Firefox.
• Linux users (Rolling Releases like Arch, Fedora, or openSUSE Tumbleweed):
  The latest version should appear in your repositories shortly.
• Manual download:
  You can always get the newest build directly from the official Mozilla Firefox Download Page.

Once installed, check out the new PDF commenting panel and semantic history search — they’re the most practical ways to experience what Firefox 145 brings to the table.

---

💬 Frequently Asked Questions (FAQs)

Q1: Is Semantic History Search available for everyone?

Not yet. It’s an experimental feature that Mozilla is gradually rolling out. You can enable it manually in the Firefox configuration settings if it’s not visible yet.

---

Q2: Does Firefox 145 require a fresh install?

No. Regular updates will automatically bring you to version 145. All your bookmarks, extensions, and settings will stay intact.

---

Q3: Can I still run Firefox on a 32-bit Linux system?

Technically, older versions will continue to function, but they won’t receive updates or security fixes. It’s strongly advised to move to a 64-bit build.

---

Q4: Is the new PDF annotation feature secure?

Yes. All PDF editing and commenting happen locally on your machine. Firefox doesn’t upload or share your files with any external service.

---

Q5: How does “Copy Link to Highlight” differ from traditional sharing?

Traditional links open an entire webpage. The new feature opens the page and scrolls directly to the highlighted text, saving time and ensuring the reader sees what’s important.

---

🧭 11. Why These Updates Matter

Mozilla’s philosophy has always been about openness, privacy, and user empowerment. Firefox 145 embodies that spirit by combining small, practical features with strong ethical underpinnings:

• Your PDF edits stay local.
• Your searches remain private.
• Your browser stays flexible.

While most of the updates may appear subtle, they collectively make the browsing experience cleaner, faster, and more personal. For both casual users and developers, Firefox 145 continues to prove that open-source innovation can compete with — and often surpass — its commercial rivals.

---

⚖️ 12. Final Thoughts

Firefox 145 is a perfect example of incremental innovation done right. It doesn’t reinvent the wheel — instead, it polishes the spokes.

From the smarter tab previews to semantic search and PDF annotations, this release focuses on practical improvements that directly impact productivity. At the same time, it maintains Mozilla’s commitment to privacy, accessibility, and web standards.

If you haven’t tried Firefox in a while, this version is a great reason to return. It’s modern, efficient, and still fully open-source — a combination that’s becoming increasingly rare.

You can download the latest version today from the official site below:
🔗 Download Firefox 145 — Mozilla Official Website

---

⚠️ Disclaimer

All features described in this article are based on the official Firefox 145 release notes. Some experimental features, such as Semantic History Search, may not be available to all users immediately. Always back up your browser data before enabling experimental flags or custom configurations.

---

#Firefox #Mozilla #WebBrowser #OpenSource #TechNews #SoftwareUpdate #Firefox145 #Privacy #Linux #WebDevelopment

Meera Joshi

Meera is a browser technology analyst with a background in QA testing for web applications. She writes detailed tutorials on Chrome, Firefox, Edge, and experimental browsers, covering privacy tweaks, extension reviews, and performance testing. Her aim is to make browsing faster and safer for all.

Website · More from this author