Thunderbird is not touch enabled as such.

Thanks. Perhaps it's time Mozilla fixed opening messages via touch as many other functions within Thunderbird are touch enabled.

Mozilla is not making Thunderbird and has not since like a decade ago so encouraging or cajoling Mozilla is rather pointless really. The saga basically starts here https://blog.lizardwrangler.com/2012/07/06/thunderbird-stability-and-community-innovation/

While there are touch enabled laptops and PC's out there, they do not necessarily make up a large percentage of Thunderbird's user base. Especially considering there is no released version for Android (Chromebooks) or IOS. Efforts in that regard I would see as more important at this time. But you are welcome to your opinion.

My Mistake. Firefox should fix it. Funny how most "touch features" do indeed work.

most touch is just an extension of mouse functions. I would have expected a double tap to work the same as a double click. But nothing Microsoft does is obvious.

I was looking through the Firefox bugs for touch and it looks like most of it is there, so would default into Thunderbird as well as they share a lot of low level code like that. So I have no idea really.