Firefox

Disable “ask AI chatbot” option in right click menu

Set browser.ml.chat.enabled to false.

Disable tab hover preview

Set browser.tabs.hoverPreview.enabled to false.

Keep browser open when closing last tab

Set browser.tabs.closeWindowWithLastTab to false.

Remove Firefox logo from new tab page

Set browser.newtabpage.activity-stream.newtabLayouts.variant-b to false.

Disable URL trimming

Set browser.urlbar.trimURLs to false.