What is the Firefox extension for managing pinned tabs?

Question

Mozilla Firefox

Hello.
At work, I use a number of web scripts that I have to constantly monitor. The scripts send email notifications, but the problem is that they don't do it by cron, but run a task when the page is opened.
I work in firefox.
I approach the issue from this side:
- We fix the tab
- When opening the browser, it opens the addresses that I set
- Periodically updates them without me on a timer
- Prohibits the transition to external sites (in these tabs)
Now the problem is that it allows you to switch to other URLs in this tab, and when you open it, it opens the last viewed page in this tab (most often already external), and if from bookmarks, then with a left click it opens in a new tab (which is correct for all except what I described).
I hope you understand me