Hopefully taco got theirs going. If not, it sounds strange the way you both had the same problem at the same time. Roku's software updates are breaking tvs. There's a green-screen thread, a black screen, a recovery loop. There's no formal bug tracking, so this more like an oral tradition.
Those customers are not getting helped at all. In fact, Roku kept pushing the update even though it was clear that tvs were being broken. I hope you don't find yourself in that category (acceptable collateral damage, as Roku views us).
Hopefully you'll work it out. It could be a hardware error. It's just strange that both of you had it at the same time. That sounds more like the other threads. If it was a hardware failure, there are videos on youtube showing how to diagnose the failed board, replace boards, etc. Shop Jimmy sells replacement boards (even the entire set for a more shotgun approach to it. That costs about $40-$80 USD depending on the tv. If you were the only person having the problem, that might make sense. But, if it was broken by Roku's untested updates, then it could be a hardware incompatibility which you'd just replace and find yourself still incompatable.
This is happening (a lot) more on TCL tvs. Roku blames TCL (even though it happened to people due to a Roku-pushed update). My theory is that TCL (maybe all tv makers -- but TCL sells more of these tvs, so we hear about it more) have revisions of boards, chipsets. Maybe they contract the manufacturing of motherboards, tcon boards in lots of thousands, to the lowest bidder. Who knows? But, something like that seems to be happening. There's some kind of underestimation of what the tv makers think Roku is testing, or capable of supporting. (And, what Roku thinks tv makers will consider "boundaries" of hardware specs. Maybe nobody even thought about this, and it's all starting to show.).
Anyway, when a TCL Roku customer is still under warranty, TCL can fix these things. They must know what the problem is (the Rev-B board doesn't work) and replace it with another board. But, when a TCL Roku customer is out of warranty, then they don't know which rev works. They might buy the same rev from ShopJimmy. Roku's no help. They just blame everything on the tv makers. You'd think they'd have a better working relationship and help sort out what the problem is. But, Roku acts like there is no problem (and waits for the affected people to leave. Then when anyone brings it up, "oh, that was so long ago. We're doing great things now! (ignore all those threads)."
Anyway, I don't want to discourage you. Hopefully you'll have a better outcome. But, I'm just saying, you could be one of the "disappeared." Brace yourself for it. Browse through 2-3 forum pages to see the lack of help Roku is. Click on Roku Danny & Mary's profiles to see their recent posting history. That's what awaits. Brace yourself.
"People are often amazed at how much we’ve done with the number of engineers we’ve got." (Roku CEO Anthony Wood, Austin Statesman, Oct 4, 2019). "Amazed" is one way of putting it.
