I mostly use postgres so I created myself a small docker image, which has the postgres client, restic and cron. It also gets a small bash script which executes pg_dump and then restic to backup the dump. pg_dump can be used while the database is used so no issues there. Restic stores the backup in a volume which points to an NFS share on my NAS. This script is called periodically by cron.
I use this image to start a backup-service alongside every database. So it's part of the docker-compose.yml
I have no direct solution to you exact problem but your usage of tabs sounds like a nightmare.
A while back I found Omnivore which works like a charm if you want to "freeze" the contents of a website to read them later. You can also self host it if you like.
I took it a step further because I love Obsidian as personal knowledge management and I want to have everything in one place. There's a plugin to sync all your saved pages from Omnivore to Obsidian. In the template for it I then have my marked highlights, the links to the version in Omnivore and the original URL and also the whole content. So I have all of that in markdown which is really nice to work with.
Maybe that's a solution you too could be happy with.