Not sure if the 10.6 is a typo however macOS 10.6 (ten.six, Snow Leopard) is ancient and Firefox support for 10.6, 10.7, 10.8 ended starting Firefox 49.0 and later with 45.9.0esr being the most current then. https://support.mozilla.org/en-US/kb/firefox-osx

macOS 10.9, 10.10, 10.11 support ended of Firefox 79.0 and later with 78.15.0esr being the most current then. https://support.mozilla.org/en-US/kb/firefox-mac-osx-users-esr

macOS 10.12, 10.13, 10.14 support is being dropped as of Firefox 116.0 and later as 115.0 ESR will be the most current. Firefox 116.0 and later will require macOS 10.15 or later. https://support.mozilla.org/en-US/kb/firefox-users-macos-1012-1013-1014-moving-to-extended-support

https://support.mozilla.org/en-US/kb/secure-website-certificate https://support.mozilla.org/en-US/kb/secure-connection-failed-firefox-did-not-connect

What web browser and version are you using to connect to the *.mozilla.org page like say https://www.mozilla.org/firefox/all/#product-desktop-release to download Firefox?

Are you using a VPN or Proxy in your connection. Some antivirus clients and such can also interfere.

I am trying to use Chrome 49 in MacOS 10.6 running in VM VirtualBox in Windows 10, all 64-bit. Even with the VPN (in the Windows) disconnected, your web site still says "A private connection to mozilla.org cannot be established because your computer's date and time ([date and time quoted]) are incorrect. NET::ERR_CERT_DATE_INVALID" with a button to summon the "Update date and time" which is useless since the date and time in my system, whether it is in the VM session or in the Windows host, is perfectly correct and always synchronized to some atomic clock or another. If the problem is with MacOS running in a VM session just say so and I will forget the whole thing. All I am trying to do is to see if I can upgrade the MacOS 10.6 to a newer version. The Safari in 10.6 appears to be considered so primitive by modern web sites that they will not even lower themselves to speak with it, and the version 49 of Chrome is refused any update by Google for being in such a depraved primitive operating system. So, I am trying to install Firefox just to see if I can get to the Apple download site to get some version of MacOS hopefully newer than Mountain Lion so that I can at least enter the 21st Century. The MacOS 10.6 is legally purchased from Apple on DVD so it is mine. I feel there is no problem wanting to upgrade to a newer version. Apparently HTTP has become kind of Republican as to who it will let into the club, now. I had downloaded the Mozilla MacOS installer in Windows, but the VM Virtualbox for some cryptic reason will not link that ISO file to let MacOS access it; the encryption appears to stymie the VM. I tried uploading the Mozilla installer ISO to my Google Drive, but once again, both the Safari and Chrome in the MacOS are being refused access to the Google Drive because they are deemed unworthy, too primitive, and gauche. So, there I am. A simple but noble experiment defeated by elitism. Thanks for your time.

Here is what appears when I try to get Virtualbox to mount the Mozilla dmg installer ISO:

Failed to open the disk image file L:\Software\Mozilla\Firefox 114.0.2.dmg.iso.

Could not open the medium 'L:\Software\Mozilla\Firefox 114.0.2.dmg.iso'.

VD: error VERR_VD_DMG_INVALID_HEADER opening image file 'L:\Software\Mozilla\Firefox 114.0.2.dmg.iso' (VERR_VD_DMG_INVALID_HEADER).

Result Code: E_FAIL (0x80004005) Component: MediumWrap Interface: IMedium {ad47ad09-787b-44ab-b343-a082a3f2dfb1} Callee: IVirtualBox {d0a0163f-e254-4e5b-a1f2-011cf991c38d} Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)

I can get into the ISO file using WinRAR and extract the dmg file, so the ISO file is not damaged. But that dmg file is not accessible to the MacOS because the VM Guest Additions are not installed because MacOS 10.6 is too primitive to install the Guest Additions plugins into, so filder sharing is not available between the MacOS and the Windows, thus rendering the available Mozilla dmg file pointless.

I have found a sort-of solution, along the line of reducing a migraine to an ordinary headache by slamming the toilet seat down repeatedly on the back of one's own head until the pain is no longer noticeable.

In Windows, the download link for any item can be copied and pasted as text into an editor. It cannot be pasted from Windows into a Virtualbox guest session, due to the lack of sharing ability if the guest session is too primitive to allow the installation of Guest Additions, but the link text can by typed by hand into the browser in the MacOS and then the download can be started. Whether the download completes or errs is another issue, but at least by 1950s standard computing this solution is workable. At least I did not have to go to an electronics shop basement to try to find a Hollerith card reader.

By the way, here is the error that appears when trying to load the Mozilla dmg ISO file into Virtualbox as a virtual disk:

Failed to open the disk image file D:\Downloads\macOSUpd10.15.1.dmg.

Could not open the medium 'D:\Downloads\macOSUpd10.15.1.dmg'.

VD: error VERR_VD_DMG_INVALID_HEADER opening image file 'D:\Downloads\macOSUpd10.15.1.dmg' (VERR_VD_DMG_INVALID_HEADER).

Result Code: E_FAIL (0x80004005) Component: MediumWrap Interface: IMedium {ad47ad09-787b-44ab-b343-a082a3f2dfb1} Callee: IVirtualBox {d0a0163f-e254-4e5b-a1f2-011cf991c38d} Callee RC: VBOX_E_OBJECT_NOT_FOUND (0x80BB0001)