Форум поддержки Firefox

I installed Firefox on a new Dell laptop and imported the bookmarks from FF on old laptp. On my old laptop things are OK. On the new laptop Firefox will ONLY store new bookmarks in the Recently Book... folder, no matter how many times I choose a specific folder from the Location dropdown, even if I only choose Bookmarks Menu without subfolder. Show Editor is checked. I have to manually move new bookmarks from Recently Book..... This is annoying. Can you help? I have not found a forum with this question.

I noticed that FireFox downloaded a Firefox HTML Document called GnT6qZGD with a size of 0KB, during this time I had tabs open from both https://wago.io/weakauras and https://www.curseforge.com/

Scanned it with Bitdefender and it was clean and when editing in notepad it is empty and a blank page when accidentally opening it.

Then completed a full system scan and it come up as clean.

I have 2 questions,

1st, Is this still a bug in Firefox that appears to have been reported before? 2nd Should I be concerned about it?

Thank you

I've made an extention which works fine when I test it using the temp mode on firefox. When I attempt to install from file however I'm told it could not be installed as it appears to be corrupt. Below are the package.json and the manifest.json:

package.json

{

 "name": "ext",
 "version": "1.0.0",
 "description": "",
 "main": "contentScript.js",
 "scripts": {
   "test": "echo \"Error: no test specified\" && exit 1"
 },
 "keywords": [],
 "author": "",
 "license": "ISC"

}

manifest.json

{

 "manifest_version": 2,
 "name": "SKUORG",
 "version": "1.0",
 "description": "Organises SKUs on WooPage",
 "permissions": [
   "activeTab",
   "webNavigation",
   "<all_urls>"
 ],
 "content_scripts": [
   {
     "matches": ["<all_urls>"],
     "js": ["contentScript.js"]
   }
 ]

}

I have tried on two devices / installs of firefox and have followed the steps I could find on this page : https://support.mozilla.org/en-US/kb/unable-install-add-ons-extensions-or-themes#w_corrupt-extension-files

If you have any suggestions please let me know.