Hi, that doesn't sound like an intentional change.

I used the green Free Download button on this page and the name wasn't modified for me:

https://www.thunderbird.net/en-US/

Is that the site you were using?

That is the same site I went to and I did click on that same button. I thought it was odd too. I tried downloading it with Edge and it saved it normally as an EXE, so it is definitely something that Firefox is doing.

I'm just not sure where to "fix" it in Firefox

I don't think there is a setting for this, and I'm puzzled why it would happen. I am not aware of any kind of file that normally has a .bin extension, at least on Windows.

Do you get the same behavior for other .exe downloads, or only on the Thunderbird site? For example, these open source programs:

• WinMerge text file compare tool: https://winmerge.org/
• 7-zip archiving tool: https://www.7-zip.org/
• Notepad++ text editor: https://notepad-plus-plus.org/downloads/

That is the first thing I thought too, did it mistakenly download a MAC file. I did a hash compare with the BIN file and the EXE that Edge downloaded and they are both the same.

All three of those files you suggested did download normally as EXEs. As a further test I tried downloading the TB102 file from Majorgeeks as they mirror it and FF saved it as a bin as well, so I'm not sure why my FF thinks that file is suspicious. It never gave any kind of warning

I notice there is a difference between how these sites characterize the file in the headers sent with the download:

• Thunderbird download: Content-Type = application/x-msdos-program
• WinMerge download: Content-Type = application/octet-stream
• 7-zip download: Content-Type = application/octet-stream
• Notepad++ download: Content-Type = application/octet-stream

What the Thunderbird site sends may be technically correct, but perhaps it is triggering the renaming on your Firefox. Why would that happen?

First, you could check the Settings page, Applications list, and see whether EXE or BIN files are defined there. Normally they are not because this list is ignored for executable file extensions.

Second, what about Windows itself? Perhaps Firefox detects that your Windows associates .bin with this Content-Type (also known as a Mime Type).

If you are familiar with the regedit.exe program, you could look at this key

HKEY_CLASSES_ROOT\.bin

and see whether it has a Content Type value (mine does not) and if so, whether it matches the one the Thunderbird site is sending.

Well I tried it on another machine here (also running FF 102) and it downloaded it normally so I can isolate it to this PC and/or FF install.

Thanks for tips on where to look in both, but I didn't see anything that would standout. Nothing in the Applications list for either of those 2 file types and the registry key was set the same as yours. I'm not sure where this troublemaker is hiding.

Hi AZBigDog, I've just tested this on a Windows machine, and it's working fine. Here's a video of my test: https://www.screencast.com/t/RXXQQKfd

We'll need some more info about your Firefox setup. Could you please follow the instructions in the following video to provide your troubleshooting information: https://youtu.be/8wKSowxEcbw

Also, you said, "I tried downloading the TB102 file from Majorgeeks as they mirror it and FF..." Unfortunately, they don't. We've had instances in the past of sites offering bad builds, because the tried to grab them from the server before the builds were verified. (Thunderbird 1.5.0.2)

Hi Chris,

I was able to narrow it down to just this machine or FF install, as it worked fine on my other one.

As for Majorgeeks I misspoke, it's not a true mirror but just a link to the official download site.

Anyway here is that troubleshooting info you requested.

https://pastebin.com/kWDjpmZm

Thanks

Hi, Unfortunately, that link has expired (or it's not public). Can you try again, and make sure it's available publicly for at least a day?

What I'm mainly looking for are any settings or add-ons that may be interfering.

Hmm odd as it said it was public. I followed the instructions in the video except for the 3 dots part as that no longer exists, so just highlighted the link and hit CTRLC.

Anyway here it is again, hopefully it comes through this time.

Thanks

https://pastebin.com/jBVVy99v

OK, I just clicked that link above and it told me that it was expired or not public which is odd as it says public and no expiration at the bottom of the options. Am I doing something wrong or missing something?

You can inspect the MIME database key with the registry editor (regedit.exe) and do a search for that MIME type (file extension) via Ctrl+F. Be cautious with editing the registry as there is NO UNDO possible: all changes are applied immediately. You can export key(s) in the registry editor before making changes. You can check specific file extension keys (e.g. .jpg or .exe) in the registry with the registry editor.

• HKEY_CLASSES_ROOT\.xxx

You can check possibly linked MIME types in the MIME Database registry key.

• HKEY_CLASSES_ROOT\MIME\Database\Content Type\

You could try https://paste.mozilla.org/, but make sure you set it to expire in at least one week.

I don't believe it is a Windows Registry thing as I can download EXE files from other sites without a problem. For some reason it is only having issues downloading EXE files from Mozilla/Thunderbird site.

OK so on the paste.mozilla.org site, I am assuming I would choose just plain text in the drop down menu and then "Paste Snippet" is what creates that link I would then copy/paste here?

yes ☺️

OK, this one should work. I still have no idea why the original pastebin would say the link was expired immediately after I created it.

Hopefully there is something in here that can shed light on my downloading issue

https://paste.mozilla.org/a2eUmanS

Thanks

Nothing in there stands out, but you do have quit a few add-ons. If you start Firefox in Troubleshoot Mode, does the problem still occur? To start in Troubleshoot Mode, go to Help > Troubleshoot Mode.

If the problem does not occur in Troubleshoot Mode, then you can disable your extensions one-by-one until you find out which one is causing the problem. For more info, visit Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.

That was the first thing I tried. It still has the same issue (again only on Mozilla and Thunderbird sites) when starting Firefox in safe mode. It is the weirdest thing why it only happens with those two sites.

On Mozilla Connect, a user reported having .mjr added to .exe files served with

Content-Type = application/x-msdos-program

I filed a bug in case that helps move this forward:

https://bugzilla.mozilla.org/show_bug.cgi?id=1778160

NOTE: Bugzilla is not for feedback or support. For more info on Bugzilla etiquette, see https://bugzilla.mozilla.org/page.cgi?id=etiquette.html

If I notice any test suggestions mentioned there, I'll update this thread.

Meanwhile, one thing you could check is the handlers.json file. This file provides the data for the Applications list on the Settings page, but there may be hidden detail in the file. Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > Help > More Troubleshooting Information
• (menu bar) Help > More Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, find the Profile Folder row. Click the "Open Folder" button on that row to launch a Windows File Explorer window.

Resize File Explorer as needed so you can see the Troubleshooting Information page behind it, then scroll down to handlers.json and drag and drop that file onto the Troubleshooting Information page to load it.

Firefox should briefly show a plain text dump, then a formatted view of the file. Normally there aren't too many entries in the file and everything is expanded. If that is not the case, click the Expand All button.

Then you can use Find (Ctrl+F) to search for msdos which normally would not appear in the file. Do you have application/x-msdos-program anywhere and if so, does it have "bin" under extensions?