Firefox 151 introduces significant privacy improvements that go beyond AI controls, with three standout changes that make this update essential for security-conscious users. According to Malwarebytes, the update includes broader protection for local network access - when websites want to communicate with devices on your local network or apps running on your machine, Firefox now asks for permission first. This feature is now rolling out to all users, not just those with Enhanced Tracking Protection set to Strict. The update also tightens defenses against browser fingerprinting in the default Standard Enhanced Tracking Protection mode, with Mozilla reporting that Firefox now limits device and browser information exposure by about 14% overall, and by roughly 49% on macOS. Additionally, Firefox 151 includes several security vulnerability fixes, with the most notable being CVE-2026-8953, a sandbox escape due to a use-after-free in the Disability Access APIs component.
Mozilla has expanded its AI control capabilities to mobile devices with the release of Firefox 151. According to reports from Business Standard, the update brings AI-related controls to Android and iOS devices, allowing users to manage tools such as translations, voice search and Mozilla's 'Shake to Summarize' feature, which generates short AI-based summaries of webpages. The update builds on Mozilla's previous approach of giving users more control over AI features rather than enabling everything by default. As reported by TechCrunch, the update allows users to turn off all generative AI functions through a single switch within the browser's settings, offering comprehensive control over AI interactions. However, Malwarebytes notes that several Firefox 151 features are "part of a progressive roll out," meaning they will appear for some users first and be expanded over time, so users may not see all features immediately.
Firefox 151 introduces significant privacy improvements including manual location selection for the browser's built-in free VPN service. As reported by Business Standard, the feature is currently rolling out for users in the US, UK, France, Germany and Canada, offering up to 50GB of data per month in supported regions. The update allows users to choose their favorite server location from the supported countries, moving beyond the previous 'Recommended' option that automatically selected the best connection. According to Mozilla, the VPN now includes a location menu listing each country where Mozilla has launched VPN support, with more countries planned for future releases. Additionally, Firefox 151 includes a new 'end private session' control in Private Browsing Mode - instead of closing every private window to clear traces, users now get a dedicated fire-icon button next to the address bar that wipes the current private session's data and starts a fresh one, clearing history, cookies, cached files, and other site data.
The update expands Mozilla's dedicated 'AI controls' section that was first introduced in Firefox 148. According to Business Standard, this feature acts as a central hub where users can review, manage or disable AI-powered tools, including a 'Block AI enhancements' toggle that stops showing AI-related prompts and suggestions. The controls are now available in iOS and Android versions for the first time, allowing users to completely turn off Firefox's AI features, enable only the features they need, or change settings later. As reported by TechCrunch, the update allows users to choose which AI-powered tools remain active, offering more detailed control over individual features. However, Malwarebytes notes that several Firefox 151 features are "part of a progressive roll out," meaning they will appear for some users first and be expanded over time, so users may not see all features immediately.
Mozilla's 'Shake to Summarize' feature is now rolling out on Android devices in English, with iOS availability in English, German, French, Spanish, Portuguese, Italian and Japanese. As reported by Business Standard, the feature allows users to quickly get a short AI-generated summary of a webpage by simply shaking their phone. The feature was first released in September 2025 for iOS and subsequently expanded with Firefox 150 on April 21, 2026, with English Android availability in Firefox 151 on May 19. According to Mozilla, the feature solves the problem of "bloated websites" by summarizing content for websites with fewer than 5000 words, helping users avoid scrolling through ads and redundant content. For iPhone 15 Pro and later with iOS 26 or later, summaries are generated on device using Apple Intelligence, while for other devices, text is sent to Mozilla's cloud-based AI and summarized by Mistral-Small.
The update reflects Mozilla's different approach compared to major technology companies that have increasingly embedded AI into products with limited opt-out options. As reported by TechCrunch, the company's latest update highlights growing consumer concerns about privacy, transparency, and the broader role of artificial intelligence in daily digital activities. The release comes amid wider public debate over the rapid expansion of generative AI technologies, with some users and privacy groups questioning whether consumers are clearly informed about how AI systems function or how their data is processed. Mozilla's decision to make AI settings more visible could place additional pressure on competitors to offer similar levels of control. The company has not indicated plans to remove AI from Firefox entirely, instead focusing on giving users the ability to decide how much AI interaction they want within the browser, aligning with its broader strategy of promoting safer, more transparent technology use. With Firefox 151's comprehensive privacy improvements and security enhancements, the browser positions itself as a more secure alternative for users concerned about browser fingerprinting and local network access.
