Felix said

Ive already set browser.tabs.insertAfterCurrent => true and browser.tabs.insertRelatedAfterCurrent = true The behavior is ... the first tab (Tab-1) created is set to the right of the active tab (Tab-A) but the 2nd tab (Tab-2) created is not. Its put to the right of Tab-1.

I have used those config settings for quite awhile and it strikes me as having "suffered" a recent slight change.

What I bolded in your posting: That seems to be the way it works in Firefox 74 for me too; and it strikes me as a change from Firefox 73 and earlier where the 2nd and subsequent new tab opened from the Active tab used to always open to the right of the previously opened new tab.

Sorry, I haven't looked for a way to revert that behavior or if it can be reverted.

Thank you for the response. I'm sorry that Firefox has no solution. I find the default difficult sometimes and hope they offer an option for this.

Thanks again