Here's a link to Plex's instructions on how to link your Tidal account to Plex:
https://support.plex.tv/articles/adding-tidal-subscriptions-to-plex/
As you'll see, there are several options. I chose the simplest, which simply links your Tidal account, and lets you use it through Plex, but does not let Plex handle the billing or otherwise manage your Tidal account. If you want that basic option, scroll down to the instructions under the heading "Link to an Existing TIDAL Subscription for Access."
Just remember that there is no Dolby Atmos support via Plex.
My other gear is all pre-Dolby Atmos, so that's not significant for me.
Just update on my Tidal and Roku issue.
My solution: (I run all audio/video through A/V receiver 4K/Dolby Atmos & Dolby Vision pass through capability)
Roku: left as is for video streaming, but I no longer stream music through it all. All basic function one remote compatible including volume & turning system on/off)
AppleTV: The shocking in a good way surprise!!! I added a AppleTV 4K gem 3 to my system in the duplicate to my Roku. Again one remote use for most functions (I have AV receiver set to 9 channel stereo when AppleTV powers on by set default). Here is the UNEXPECTED RESULT: MUSIC SOUNDS SO MUCH BETTER!!! Clearer, more detailed and nuanced music, it like I upgraded my speakers, I hearing music tracks I listened to for years for the first time, while Tidal in Roku sounded great with my audiophile sound system, the change in sound quality from Hi-Res streaming on the AppleTV is getting all the details, it was completely worth buying the AppleTV just for the increase in loss-less sound quality.
BOTTOM LINE. Still love my Roku for streaming TV, a much better interface, but for music, the improvements in are worth streaming music via AppleTV instead, and assuming ChromeCast has same potential as still also has Tidal. The new Tidal app in zBeta form is a huge improvement over the app we knew in Roku.
Finding switching between the 2 streaming boxes is symbols with automatic connecting of each streamers remote to high end AV Receiver (oddly the Tidal built into my receiver sounds the same as Tidal did in Roku, given by receiver is about 7 years old I guess Hi-Res streaming hardware capabilities have improved, who knew I missing such great audio playback potential. My understanding is Roku and Fire hardware just is not up to the task of maximum playback potential. I was angry at first, but feeling the change was a surprise for the best. Hopefully next gen Roku will be fully compatible, but until then delighted with AppleTV fir streaming Roku eith better interface on the new app
Hope some of you find this helpful, based on my experience.
Cheers
Apparently Tidal is pulling the plug on app support for multiple platforms including Roku
https://www.flatpanelshd.com/news.php?subaction=showfull&id=1719466297