Hi Mark,
This is Wil, one of the independent advisor, an expert with Windows 10 and a fellow Windows 10 user like you. I understand your concern about restoring 50 tabs on Google Chrome.
If your Google Chrome crashed or closed all 50 tabs at the same time by closing Google Chrome itself, you may still retrieve it if it is still on the History.
You may press CTRL+SHIFT+T to reopen the recently closed tabs. If the 50 tabs are your most recently closed, Chrome should open it. You may also click on the three vertical dots on the upper-right part of Chrome and hover your mouse on the History and should see on the list "50 tabs". If there's none, unfortunately, the only way to retrieve them is one at a time on the browsing history (CTRL+H)
I hope the information I provided will help you. If you need further assistance please do reply back and I will respond as quickly as possible. Have a nice day.
Thanks,
Wilfred P.
Independent Advisor