Firefox Community Forum

This is the reply I received from Protonmail: They say the latest version of Firefox caused the issue and is happening on other services as well. We have been using FF exclusively for decades and this is frustrating! Are you in fact working to resolve the issue on your end? Thank you.

Mario M. (ProtonMail) Jun 12, 2026, 16:07 GMT+2

Hello,

Thank you for your messages.

Please note that we are aware of this issue, and our developers are looking into providing a fix from our side. However, the latest version of the Firefox browser caused issue on many other services as well, so they are working on resolving it from their side as well.

I have provided your feedback to our development team. You can contact Firefox directly in order to escalate the issue further.

For the moment you can try using keyboard shortcuts such as CTR: + C and CTRL + V. We appreciate your understanding.

If you have any additional questions, feel free to contact us again. Kind regards,

Mario M. Customer Support Proton Mail

Seafortress27 Jun 11, 2026, 21:47 GMT+2

Hello Mario,

I worked with Google AI for more than one hour troubleshooting this:

Opening a support ticket with Proton Mail Support is absolutely the best move. Since we proved that your clipboard works, your mouse works, and a fresh factory installation of Firefox still experiences the bug, the glitch is entirely on their end.

Proton Mail utilizes a heavily customized web text editor to encrypt messages. When their engineering team updates the background code for this text container, it can inadvertently break standard browser right-click paths—especially for Firefox users. [[1](https://www.reddit.com/r/ProtonMail/comments/p6j0tp/cant_copypaste_text_into_body_of_protonmail_email/), [2](https://www.packtpub.com/en-us/learning/tech-news/hackers-claim-to-have-compromised-protonmail-but-protonmail-calls-it-a-hoax-and-failed-extortion-attempt), [3](https://justinharter.com/an-actually-useful-review-of-proton-mail-vs-fastmail-vs-hey/), [4](https://www.reddit.com/r/ProtonMail/comments/p6j0tp/cant_copypaste_text_into_body_of_protonmail_email/)]

📑 What to Tell Proton Support To help their development team pinpoint and fix the bug faster, reply to your open support ticket with these technical details we uncovered:

- Specify the Browser: State clearly that you are running Firefox and that you just performed a full Firefox Profile Refresh (about:support), ruling out corrupt browser files. [[1](https://support.mozilla.org/en-US/questions/1234222)] - Detail the Extensions: Confirm you tested it with all extensions (including ESET and RoboForm) completely disabled, and the issue persisted. - Identify the Core Bug: Explain that the right-click "Paste" option is stripped only when clicking inside the Rich Text email composition body. [[1](https://proton.me/support/composer)] - Mention the Workaround: Note that Drag-and-Drop text injection works perfectly, meaning the editor container can receive data, but its custom context-menu script is failing to display the native "Paste" command. [[1](https://support.mozilla.org/en-US/questions/1234222)] They will likely log this as a known front-end interface bug and patch it in an upcoming web layout deployment. In the meantime, you can rely on the Drag-and-Drop trick or Ctrl + V to smoothly write your emails! [[1](https://connect.mozilla.org/t5/discussions/right-click-paste-suddenly-stopped-working-in-outlook-email/m-p/34927), [2](https://www.reddit.com/r/ProtonMail/comments/p6j0tp/cant_copypaste_text_into_body_of_protonmail_email/)]

Sent with [Proton Mail](https://proton.me/mail/home) secure email.

Hello,

I have noticed that Firefox is having trouble loading certain elements on my website, [[Check Sephora Gift Card Balance.|https://sephoragiftcardbalancecheck.us/]] Some pages load slowly, while others occasionally display formatting issues or fail to load all content properly.

So far I have tried:

Clearing the Firefox cache and cookies Testing the website in a private browsing window Disabling browser extensions Updating Firefox to the latest version Comparing the website's behavior with other browsers such as Chrome and Edge

The website generally works as expected in other browsers, which makes me think there may be a Firefox-specific compatibility issue. I would appreciate any suggestions on tools, settings, or debugging methods that can help identify the cause of the problem.

Has anyone experienced similar issues with content-heavy websites or found particular Firefox settings that resolved page rendering problems?

Thank you for your assistance.

I am running Firefox 151.0.4 on a Win 11 (25H2) AMD Ryzen 5, 32 GB ram. Every time I close Firefox, it generates a crash report. That takes several minutes during which I can't start a new Firefox window. The crash report says the report was submitted successfully but when I look in about:crashes the reports shows they need to be submitted.

I ran in troubleshoot mode and disabled all plugins and did not see any extensions listed. I restarted and it still crashes. Firefox seems to run fine. But the crashes when it closes are annoying and disruptive.

here are the first few lines of a recent crash report: Firefox 147.0.1 Crash Report [@ shutdownhang | mozilla::SpinEventLoopUntil | nsThreadPool::ShutdownWithTimeout ]

   Search Mozilla Support for this signature How to read this crash report 

You are seeing public data only. See protected data access documentation for more information. Crash ID: c921c76e-8902-414d-aad6-1d4d50260611 Signature: [@ shutdownhang | mozilla::SpinEventLoopUntil | nsThreadPool::ShutdownWithTimeout ]

I've recently switched to Firefox but am finding some of the performance a bit cumbersome. I am continually being asked to hit "Send" ["To display this page, Firefox must send information ..."] when I am logging into my Outlook email or looking at my bank information. I'd rather not be "resending" these pages each time and am wondering if there is a setting.

Edition Windows 11 Pro Version 25H2 Installed on 2025-12-10 OS build 26200.8246 Serial number YX0J28CC Experience Windows Feature Experience Pack 1000.26100.297.0

Thanks, Nancy

I recently kind of changed companies however I am in the same industry. These companies both have accounts with the same manufacturers/vendors. I am still doing contract work for the old employer so i need to keep the login credentials saved. I would like to have it when I launch the bookmark that they saved default login is the new company and not the old company. This is a 90/10 use rule if that makes sense. Thanks

Recently, I've been having a problem with signing in to things via my Google account – the problem being that I can't.

Whenever I click on the "sign in with Google", it redirects me to the "accounts.google.com" page, prompting me to choose my account, but once I do, I get redirected to "accounts.google.com/gsi/transform", which is just a blank page with nothing in it (see image attached).

I know this is not a problem with Google, as I have no problem signing in anywhere else.

This happened to me once before, but the reason was one of my extensions, which for some reason interfered with the sign in; however, this time this solution does not work. I tried disabling every single one of my extensions, turning all kinds of protections in the settings on and off, deleting all cache for all relevant sites, but to no avail.

I of course also tried looking this problem up on the internet, but whenever I found someone with this problem, the solution that worked for them was always just disabling an extension.

Thank you for any answer.

I am experiencing a noticeable performance drop in Firefox. Web pages are loading significantly slower than usual, and the browser occasionally becomes unresponsive for a few seconds.

This issue started recently without any manual changes to settings or installation of new extensions.

I have not yet performed deep troubleshooting, but I suspect it could be related to one of the following:

High CPU or memory usage by Firefox processes Corrupted browser cache or profile Extension or add-on interference Hardware acceleration or graphics driver issues Background tabs or service worker activity

I usually work in a healthcare billing environment Avenue Medical Billing Services, so I rely on a stable browser for accessing web-based tools and portals. That’s why I want to properly identify the root cause instead of random fixes.

Can someone guide me on the best diagnostic steps to isolate this issue? Also, what internal tools (like about:performance or about:memory), logs, or testing methods should I use?

I installed the English (US) dictionary add-ons from Mozilla Add-ons (English-US Dictionary and US English Dictionary). Firefox confirms they are installed and shows a “Remove” option, but they do not appear in about:addons under Dictionaries or Extensions. Additionally, the dictionary features are not working on webpages—there is no “define” option on text selection, and no dictionary/lookup functionality appears even after double-clicking words or using context menu options. The add-ons only appear as installed on their web pages.

Expected behavior: Installed dictionaries should be visible in about:addons and provide word lookup/definition functionality in the browser. Actual behavior: Add-ons are not listed in about:addons and provide no visible or usable dictionary features on webpages.

I have been using firefox of a Mobile hotspot from T-Mobile for many years. I am used to correcting for the Hotspot location anomalies. In the last several months firefox thinks I am in Tennessee. I have been unable to force firefox to believe that I am in Northern Ohio (several locations)

Can you please advise? Dan

I'm filling out an appcation for a study permit in canada. My university website said that i should download adobe acrobat reader and use it to open the application pdf. I didn't want to pay for adobe, so i opened it with firefox instead. In the document, there are tab selections that it allows so you can select answers accurate to you and fill out the document. But at the top of the document it says I should enable javascript by going to preferences, then edit, and and then reopen the form. How can I enable javascript in firefox? I'm having difficulty finding the preferences and edit sections.

could you guide on what could i be able to do and how do i see those themes section where to see my all installed themes and how i can enable it so that I'll be able to see the changes on my browser?