If the ugs are fixe
My browser shuts down and video keeps playing. The browser can be stubborn to open and at times doesn. But I looks and feels good, once you get the improvements I hope it exceeds Opera. I stopped using Opera. It became really inferior.
Your first post, so welcome!
When Vivaldi crashes or disappears and won't restart, check for any vivaldi.exe processes that remain open (via Windows Task Manager or Sysinternals Process Explorer). If you find any, you will need to terminate them before Vivaldi will start again.
If you're using Technical Preview 2 (v.188.8.131.52) as most new users are, try updating to the most recent Developer snapshot (v184.108.40.206). This was just released today (Apr. 17, 2015), and isn't yet as well tested as the previous release (v220.127.116.11), which was quite stable and would be a good choice if you want to be more cautious.
Vivaldi is developing rapidly and there have been numerous bug fixes and feature improvements since Technical Preview 2. Developer snapshots since then have generally been as stable, if not more stable, than TP2.
Follow the Team Blog for weekly updates (usually on Mondays) and occasional mid-week updates.
I hope so, many other browsers really suck. I miss the old Opera.