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Firefox usually keeps you signed in through cookies saved by the website. If Firefox, an extension, or another utility deletes those cookies, the site may ask you to log in again. To answer “Why does Firefox keep logging me out of websites?”, first check whether it happens on one site or many, and whether it follows closing Firefox. Then inspect cookie, history, and private-browsing settings before testing add-ons or cleanup software.
Start by identifying when Firefox loses the sign-in
Note whether the problem affects one website or several, and whether it happens while Firefox remains open or only after you quit and reopen it. This pattern helps narrow where to look; it does not identify a cause by itself.
- One site: Begin by checking that site’s stored data.
- Several sites, especially after closing Firefox: Check browser-wide cookie, history, and private-browsing behavior.
- Sign-outs during an open session: Check the affected site’s data and then investigate extensions or other software that may manage cookies.
Cookies can store login status, allowing a site to recognize you on a later visit. If that cookie is removed, the site may no longer remember the sign-in. Mozilla explains how cookies work.
Check Firefox’s cookie and site-data settings
Open Menu → Settings → Privacy & Security, then find Cookies and Site Data. Review whether Firefox is set to delete cookies or site data, particularly when Firefox closes. Labels and available controls can vary by Firefox version and operating system, so use the options shown in your own Settings page.
#1 Best Overall
- Compatible Model(s): Magicmoon brand filter only for 24 inch -diagonally measured - widescreen monitor - aspect ratio 16:9 - filter size: width: 20 15/16", Height: 11 13/16" (531mm x 298mm)
- Superior Privacy: The computer privacy filter makes the screen appear dark when looking at it from an angle (the angle is about 30 to 60 degree), but bright when looking directly at it. To change the privacy level - simply adjust your monitor’s brightness accordingly
- Eye and Screen Protection: Privacy Filter does not only protect your private life but also protects your eyes by blocking 30% of blue light , blocking the harmful blue light between 380 to 495 nm, it filters out the blue light and relieves eye strain
- Perfect For Open Workspaces: Great for maintaining screen privacy in open work spaces
- Includes Two Options: Option 1 uses clear adhesive strips that securely attach to any computer screen. Option 2 (for computer screens with a raised bezel only) uses slide mount tabs that easily stick to the display frame, allowing you to slide the privacy screen filter on and off as needed
Mozilla’s cookie and site-data instructions explain how to manage stored data, including data for selected websites. Avoid clearing all site data as a first step: deleting cookies can sign you out and remove site preferences.
Check private browsing and clear-on-close behavior
Private browsing does not retain the same browsing data after the private session ends. Also review whether Firefox is configured to clear history when it closes, and whether that behavior includes cookies or site data. Mozilla Support community discussions identify private browsing and close-time clearing as possible explanations for lost sign-ins, but they are troubleshooting suggestions rather than a definitive diagnosis for every case. Check the controls in your current Firefox version rather than relying on checkbox names from an older discussion.
Rank #2
- 【Privacy Filter Dimensions】- Width: 20 15/16" (532 mm), Height: 11 13/16" (299 mm), Diagonal: 24" (609.6 mm) - SightPro Blackout Privacy Screen Filter is engineered to be compatible with HP, Dell, Samsung, Lenovo, LG, Acer, ASUS, ViewSonic, and other monitor brands. Please verify your computer screen's width and height measurements before ordering. It's not recommended to make your selection based solely on your computer screen's diagonal size.
- 【Two Attachment Options】- Installs in minutes. Option 1 uses clear adhesive strips that securely attach to any computer screen. Option 2 (for computer screens with a raised bezel only) uses slide mount tabs that easily stick to the display frame, allowing you to slide the privacy screen filter on and off as needed.
- 【Superior Privacy and Anti Glare】- Our advanced multi-layered film filter blacks out your computer screen when viewing from the side, while maintaining a crystal clear screen straight-on. It also protects your eyes from harmful glare, UV, and blue light. [Note: It does not block visibility directly behind you, regardless of the distance.]
- 【Perfect for Travel and Open Workspaces】- Our computer screen privacy filter is the ideal solution for healthcare providers, mobile workers, commuters, students, and business travelers. Now you can stay compliant and safeguard sensitive corporate information while working in airplanes, subways, airports and public areas.
- 【Package Contents】- Each package includes one privacy screen shield filter, two sets of clear adhesive strips, two sets of slide mount tabs, and a microfiber cleaning cloth. Buy with confidence – located in the US, Sight Pro specializes in providing best-in-class privacy solutions to individuals, small businesses, corporations, government, and educational institutions. Our privacy screens are Section 889 and TAA compliant.
If only one website logs you out, inspect its stored data
In Settings → Privacy & Security → Cookies and Site Data, use the site-data management control to look for the affected website. Removing only that site’s data can help address a site-specific problem without clearing data for every website. Be prepared to sign in again: clearing that site’s cookies and data removes its saved session and may also erase preferences.
Free tools Windows power users keep installed
One-click scans. No signup required.
Mozilla provides steps for managing and clearing site data. If you remove the site’s data, return to it, sign in, and check whether the sign-in lasts as expected.
Rank #3
![[2 Pack] 24 Inch Computer Privacy Screen Filter for 16:9 Widescreen Monitor](https://m.media-amazon.com/images/I/41SBKw3J4ML._SL160_.jpg)
- 【24 PRIVACY FILTER DIMENSIONS】 Width: 20 15/16" (20.9 inches/532 mm), Height: 11 13/16" (11.8 inches/299 mm) - 16:9 Aspect Ratio. Mamol computer privacy filters are designed to be perfectly compatible with HP, Samsung, Dell, Lenovo, Acer, Asus, LG, ViewSonic and other brands of monitors. Please check the width and height dimensions of your computer screen before ordering. If you have any questions about the dimensions, please contact us.
- 【ENHANCED PRIVACY PROTECTION】Mamol 24 inch computer privacy filter keeps your electronic information confidential, making it excellent for use in high traffic areas. the computer privacy screen 24 inch is designed with advanced microlouver technology to block visibility at around 30 degrees and black out screens completely near 60 degrees.
- 【EYES PROTECTION】 This blackout privacy screen greatly reduces eye strain and minimizes potential hazards to vision. It filters 99.9% of UV rays and suppresses 98% of blue light. As a reversible 24-inch privacy screen filter: The glossy side of the protector provides extra clarity and greater privacy, and the matte side minimizes glare and distracting reflections. Satisfy your different daily uses as needed.
- 【BETTER HD CLARTIY】Mamol 24 inch computer privacy screen Shield adds an extra layer of AR Ultra HD light transmission compared to others. It maintains the high definition of the screen without sacrificing too much screen brightness. It won't reduce the brightness and cause eye fatigue because of the privacy screen installed on the screen.
- 【ANTI SCRATCH & WASHABLE 】Our privacy anti-glare Monitor film has a surface enhancement layer to protect the privacy filter from scratches and fingerprints. It is washable and reusable. Even after prolonged use, you will get a brand new privacy screen for your desktop computer monitor after cleaning. Very Durable!
If the settings look right, test extensions and related software
A cookie-control add-on or external privacy, security, or cleanup utility may remove cookies independently of Firefox’s ordinary settings. Mozilla also recommends Troubleshoot Mode when diagnosing Firefox problems. Open Menu → Help → Troubleshoot Mode and restart Firefox when prompted. If the sign-out stops in Troubleshoot Mode, investigate extensions, themes, and hardware acceleration; Mozilla notes that these can affect site behavior. Mozilla’s troubleshooting guide explains the mode and how to continue diagnosis.
Change one thing at a time. Review cookie-managing extensions and cleanup utilities first, then retest before changing another setting. Avoid running a cookie-cleaning tool while diagnosing persistent sign-outs, because deleting cookies can recreate the problem.
Rank #4
- Privacy Screen Filter Size: If the visible area of your display has the following dimension: Width x Height (Exclude Frame/Arrow 1 to 3 mm errors): 20 15/16" x 11 13/16" (532 mm x 299 mm), then this filter is good for you. Very Important to double check your screen's Width and Height excluding frame before ordering. It's not recommended to make your selection based solely on your screen's diagonal size
- Left and Right Privacy: Not block visibility directly behind you, regardless of distance. The privacy filter makes the screen appear dark when looking at it from an angle (left and right 30 to 180 degree), but clear when looking directly at it. To change the privacy levels, simply adjust your monitor's brightness level accordingly
- Matte and Glossy Sides: It's a reversible privacy screen filter, giving you the flexibility to choose glossy or matte finish. The matte side will have less glare, however the glossy side will have stronger privacy
- Perfect for Open Workspaces: Ensure your working space is bright and well lit. Privacy screens do not work in dimly lit areas
- Two Installation Option: Option 1 uses clear double side adhesive strips that securely attach to any computer screen. Option 2 (for computer screens with a raised bezel only) uses slide mount tabs that easily stick to the display frame, allowing you to take out the privacy screen filter easily as needed
Retest the sign-in after each change
- Sign in to the affected website.
- Repeat the condition that usually triggers the sign-out: wait while Firefox stays open, or close and reopen Firefox if the problem follows a restart.
- Check whether the site still recognizes you.
- If the problem remains, continue to the next relevant branch: site-specific data for one site, browser-wide retention settings for several sites, or extensions and cleanup software when settings appear correct.
Firefox sign-outs can have more than one cause; the pattern helps prioritize checks, but does not prove which setting or utility is responsible.
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Quick Recap
Best Value
![[2-Pack] 24 Inch Computer Privacy Screen Filter for 16:9 Widescreen Monitor](https://m.media-amazon.com/images/I/41jLN+QeBGL._SL160_.jpg)
- 【Improved Privacy Filter】Protescreen 24 inch privacy screen filter after 200 times updates,Use revolutionary micro-louver technology. The 24 inch computer privacy filter limits viewing angle to +/- 28° and provide clear vision on the front. If see from the sides, the greater the angle the darker the screen.Anyone who tries to peek over the side will only see a dark screen! So with a computer privacy screen protector 24 inch, the privacy of your computer screen will never be leaked.
- 【Package Content】You can get 2pcs 24 inch computer monitor privacy screen filter for a better price! Each package includes 24 inch privacy screen film x2, adhesive strips x2, slide mount tabs x2, alcohol x2, cleaning cloth x2. We are a factory that integrates production, processing and sales, We guarantee that all of our products are premium privacy screen protector. If anything happens, we will send you a new 24 inch monitor privacy screen at absolutely no cost. So you can buy with confidence!
- 【Eyes Protection & Anti scratch】Computer screen privacy shield 24 inch monitor use filtering optical materials imported from Japan can reduce 92% of blue light and 98% of UV light, and filter all harmful light emitted from the screen.The high-transparent and reinforced built-in protective layer not only presents high-definition picture quality, but also protects your screen from scratches.Hurry up and place an order, Own privacy screen for computer monitor 24 inch, Protect your screen and eyes.
- 【Brilliant Anti-glare & Function Options】Our privacy screen protector for computer 24 inch monitor protects your eyes by blocking 95% of reflected light. Create a clear and transparent visual space and reduce eye damage by glare. And It is a reversible privacy screen filter. A matte surface effectively prevents blue light and glare, while a glossy is more privacy-resistant. You can choose flexibly according to your needs. In addition to this it also protects your screen from dust and scratches.
- 【Easy to Install & Reusable】Our 24 inch privacy screen for monitor has 2 uniquely designed installation methods: ① Permanent installation- double sided adhesive tape. Suitable for all computers with a screen aspect ratio of 16:9 and a size of 24 inches. ② Removable installation- slide mount tab. Suitable for computer with raised frame, you can slide the filter in and out of the screen as needed, it provide a quick and easy way to remove your monitor privacy filter when you don't need.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
