I've followed watchdog's tutorial above, to the letter. Installed the current 'stable' .deb to DPup Stretch. Modified /opt/vivaldi/vivaldi to add the '--no-sandbox' switch. You must then either start Vivaldi (to create a profile), or create /root/.config/vivaldi, and copy the contents of an existing Vivaldi profile into it.
If you don't have a profile, the update scripts will hang.....because each script writes a small text file to your profile which confirms the upgrade to the browser. If already running, close Vivaldi while you run the update scripts; if you've copied a profile, run them before starting up.
Start Vivaldi.
Go to 'chrome://components', and Widevine shows as up-to-date. Close the tab. Go to NetFlix, sign in, and try to watch something. You'll get the usual 'Can't find Widevine....', etc. Close the tab. Go into 'chrome://components' again, and click on the Widevine 'Check for updates' button. It'll say 'Component not updated' (because it already is), but the act of doing so now means that Vivaldi will see it, because it creates a text file in your profile which tells the browser it's been updated.
Go back to NetFlix again, wash, rinse & repeat. All things being equal, everything should now be working.....
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I'll be releasing the new version of Vivaldi-portable soon, this time using the update scripts, albeit in a slightly different way. With the portable, if you try running the scripts from their normal location inside the /vivaldi directory, it'll overwrite your existing profile & create a new one.....which is rather annoying, 'cos you'll lose all your bookmarks, etc. Don't ask me why this happens; I'm not enough of a 'script-jockey' to fully understand what the script is doing, but I've found a way that'll work with minimal messing around. It just involves running the scripts from an unrelated location, followed by manually re-locating two files.
Stay tuned.
Mike.
