Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

While still in Safe Mode,

In the address bar, type about:crashes<enter>.

Note: If any reports do not have BP in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most resent 7 - 10 crash reports, and copy them. Now go to the reply box and paste them in.

For more help on crash reports, see; https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support +++++++++++++++++++++++ If you can't get Firefox to open, you will have to do this the hard way.

https://support.mozilla.org/en-US/kb/mozillacrashreporter Open the file browser / explorer on your computer. Note: You may have to enable Show Hidden Folders / Files. Enter this in the address bar;

Windows: %APPDATA%\Mozilla\Firefox\Crash Reports\submitted Win 7/Vista: C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Crash Reports\submitted Win XP/2000: C:\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Crash Reports\submitted

Mac OS: /Users/<username>/Library/Application Support/Firefox/Crash Reports/submitted Linux: /home/<username>/.mozilla/firefox/Crash Reports/submitted

Copy the most recent 5-7 File Names in the folder. Post the information in the reply box.

Start Firefox in Safe Mode by holding down the <Shift> key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode. Is the problem still there?

• Yes it is.
• At first came the dialog “FF is not your standard browser…”
• After clicking “…later…” FF started to crash immediately as described earlier.
• I closed the next dialog with the “X”
• Second try: “start in save mode” >> Starting to crash (means: the chosen start-Tabs opened for less than 0,5 seconds and then the error-dialog appears.
• This means, the next steps could not be performed:

Omitted

• Here are the submitted files, retrieved "the hard way":

bp-2a8d2c5a-6216-41d6-b4e3-210310180419.txt bp-2b83141e-8cf1-4bcd-aee3-685561180419.txt bp-4f19965e-5c56-4ce8-a352-8f2431180419.txt bp-75c0f70f-cd65-4bf8-b643-1d4011180419.txt bp-808ddcd1-657c-4a8e-961d-03e630180419.txt bp-00951f75-5bc7-4703-a02b-6f44a1180419.txt bp-27508e6e-996a-4b30-bd9f-5f5522160722.txt bp-652831d7-869c-4c29-8af3-6323d1180419.txt bp-1471003b-1bdf-43e2-815b-f691f1180419.txt bp-bc632fee-c190-4ff3-b827-acbfb0180419.txt bp-c3b4398f-afdc-4afa-ac68-258391180419.txt bp-d3c68d17-eb1b-4b7c-8e79-434a31180419.txt bp-df648d34-49ce-40b5-a783-3b0961180328.txt

That was very good work.

Product Firefox Release Channel release Version 59.0.2 Build ID 20180323154952 OS Windows 10 OS Version 10.0.16299

bp-2a8d2c5a-6216-41d6-b4e3-210310180419 bp-2b83141e-8cf1-4bcd-aee3-685561180419 bp-4f19965e-5c56-4ce8-a352-8f2431180419

Signature: TaskbarList::SetThumbnailTooltip

Let’s do a full clean re-install;

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86)

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia