At least it is more usable now, but there are still a lot of issues - most already mentioned.
But at least we can start music now.
Applications like Yatse are able to access Plex libraries and works with AA.
I am giving it a try and so far so good.
Would this solve all the limitations we are struggling with when using Plex in AA ?
I found out the issue with why Plex on Android Auto will not display all playlists. In fact this is an issue with all apps with playlists through Android Auto.
Android Auto will force the apps to truncate playlists or song lists while driving, even while braked (say at a stop light). Only when going into full park does the list actually return as normal for Plex or any other apps that I used such as PlayerPro.
On my end, I fixed this issue by rooting a Moto G7, installing a version of Xposed Framework ported to Android 9 Pie, and then setting up Sensible Android Auto: Xposed, all of which disabled the forced limits of displaying playlists in my car while driving.
I’ve been using this for a week and it has been perfect ever since.
Just a bit of background of my intent.
I bought a cheap Android, the Moto G7 (which by the way has a most excellent screen and great performance) and turned it into a dedicated Android Media System for my car which has a built-in system with USB that natively supports Android Auto.
This phone does not have any service, instead I have it tethered to my actual phone if I want to stream Plex playlists from home. When I get home, parked in my garage, it connects to my local WiFi which I use AirDroid/AirMirror to manage and update any G7’s local music and playlists.
This setup worked out great, but of course the initial playlist limits almost ruined everything – until rooting it.
I now have the phone hooked up to my car through USB permanently, it’s mounted under the dashboard hidden from view, and without any cell service, and with only running WiFi, and with the screen on the lowest dim setting so it doesn’t sleep, it doesn’t drain quickly when the car isn’t on, and my car’s system connects to Android Auto immediately upon start.
My commute to work is more than enough to fully charge this phone in this state and has yet to hit below 90%.
Yes, Artists selection is gone… which made Plex useless in AA
absolutely intentional and without explanation … unfortunately I have to repeat myself…they think of us as trees where dogs can piss …
So far all good.
Yes, I am having issue wuth thumbnails /posters not properly displayed in AA - fixed, i have downloaded all thumbnails to offline cache using Library settings >Expert >Manage cache
This seems to resolve the problem
Also Recently played does not seem to work for me in Yatse (same in Plex)…
Same here… No artist option anymore. This is like complaining to your doctor about elbow pain, so he amputates your arm. Plex is completely useless on AA for me now.
I’m with you @ussalin, this is ridiculous. Plex is useless in AA, and having to remember to not upgrade the old 7.10 version is so tedious.
Glad I paid for Plex Pass 
Hey, I wanted to bring a bit of information about why the “Artists” AA entry has been recently removed.
As some of you already know, any AA content section that might contain quite some content could cause issues when loading. I already explained the technical reasons/issues behind the problem (basically, AA integration is not meant to display long lists of elements, and internally the integration fails when loading lists with ~200 or more elements). For playlists and other sections, we’ve manually limited the amount of elements returned to avoid such issue, but that’s not something we can do for “Artists”, as such section was meant to display all your artists (there is no point manually limiting the amount of artists displayed from your collection). Also, the AA integration doesn’t support any paging capability unfortunately, so as far as we know there could not be plan B for keeping it.
Therefore, and following the AA integration UX guides, we decided to remove the “Artists” entry altogether, based on the fact that users can still access to artists from other sections (“Recently added/played artists”) and to all of them using the voice search integration.
We apologise for any problem caused by this, but it was the best decision possible given the limitations/restrictions found.
The latest beta release of Yatse has a strong impact on AA and puts a tombstone on the discussions of these months: Artists Playlists Albums Recently Played all correctly visible … really a great job 
Yatse does not display Artists/Albums if there are many elements.
So does this mean that there are no plans to return the AA app to working order? Do you guys realize that the app is practically unusable at this point?
As mentioned, it is a limitation of the Android Auto interface. Any long lists will not work. There is no way to make these lists work unless Google changes Android Auto to handle long lists better.
with the last beta?
Just FYI, Yatse is using an intermediate menu to solve the problem, and it works fine.
Another issue - and this may just be me - is that voice search has never worked with Plex on AA. If I could say “Plex, play Simon & Garfunkle,” that would probably suffice; instead, it always, without fail brings up some stupid podcast I didn’t want to listen to.
Finally, most recently, one of my music libraries (the large one) has simply disappeared from AA. It shows up fine in Yatse.
The last update to Plex made a SMALL step towards becoming operational in AA. There lots further to go! Here are my top issues.
None of these 3 issues are caused by the “big list” issue. That is not an acceptable excuse. Come on Plex. Get this stuff fixed!
And while you’re at it, how about a widget!
Do you keep the phone connected or not? It has been said that if unplugged and then replugged the phone the song resume…but in my case I have the device always connected and there is no way to recover the song …
In the scenario I described, the phone is disconnected during the stop. There is no way in AA to continue where you left off. To get anything playing I have to restart the playlist. And since that is not shuffled, the is the same music all over again.
1 - Picking a playlist should bring up the player interface and start playing all. If you slide up on the page you then get the shuffle option. Resuming a playlist is something Plex doesn’t do. I’m personally hoping this will become a feature in the future.
2 - I can confirm this behavior. Let me check if this is intended or a bug.
3 - I can also confirm this. I don’t know if it’s an AA limitation or something with Plex. I’ll have to check and get back to you.
To add a little more detail here…Plex is actually ready to resume play, but there’s no way in AA to resume since neither the home screen Audio tile not the player interface on the Audio tab are shown. As a work-around, I have pulled down the notification bar and resumed play from the Plex notification tile. The music resumes although there are still no interface elements in AA until the Plex advances to the next track. Then all the expected interface elements appear!
FWIW…many other media players work properly in this regard - Google Play, PocketCast and Yatse among them. In the case of Plex, it will not show any paused track in AA that AA has already seen once. To demonstrate -
You can release these steps for ever and the cycle continues. Steps 2 and 4 can also be repeated as many time as you want. Bottom line…You only see the AA interface elements for the player the first time AA sees the track. It is as if the “Notification” indicating a playing/paused track is only put out there once and when AA sees it the first time, that notification is gone, stale, or otherwise used up as far as AA is concerned. Other apps apparently refresh or replenish the notification.
