It would be useful to have the posts be collapsible. The popular internet site "reddit" does this, and it makes viewing a threaded conversation much easier.

...a overview and detail view to somewhat customize the way it looks. Flat mode is the one that causes all the confusion. It is in strict chronolical order and threads bump up with a new reply. I recommend Tree mode. Overview only shows the subject of the originating post. Detail view shows the OP and replies.

Some of us (waves hand!) have been suggesting that TER switch to modern, up-to-date, consortia maintained and improved open source forum software for several years (waves hand!!). Such forum software usually includes an internal mail ("Private Mail") system with more features (searching, sorting) than current TER PM.  
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It would be a BIG change, but they would only have to do it once.  Instead, we get what appears to be more home-brewed forum software.  A small group of in-house programmers (or contract programmers) can't compete with the global consortia who continuously revise, improve, debug ... the open source platforms.
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I can't find the Overview - Details buttons in new/Beta. Where are they?

The "Overview" button is on the far right next to the "+New Thread" button. However, It only shows when you are in Tree mode. When you are in Flat mode it isn't visible. I hadn't noticed this because I always go to Tree mode as soon as I log in. (I like the Tree mode in "New" TER.) When you click the "Overview" button you only see the subject of the originating post and the "Overview" button becomes the "Detail View" button.
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I checked this on my Kindle and my laptop.
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BTW: thanks for the post about CR then . (period) to get a double space between paragraphs. I thought I was losing it when I was sure I had hit enter twice but the space didn't show up when I hit post message.

...it keeps the replies in proper alignment with the post they are replying to.