When I am on the forum page, I like to look at the “latest” section. There old threads with new post.
When I click on an old thread with a new post, it automatically opens the first post. Why? Then I have to scroll all the way to the bottom to see the latest post. You would think it would open to the latest post automatically when you click on an updated thread.
I am missing that feature as well. 
There is a little scroll down “bar” on the right that you can slide down to get to the bottom of the thread, but it doesn’t take you to the exact post where you last left off.
By default you’ll go to the last reply you read. (Unfortunately, that data didn’t make the migration to the new forums. From now on it should remember where you left off.) But you can also jump to the last post by clicking on the last reply date. You should also see a “back” button to take you to the spot you left off: What does the timeline back button do? - support - Discourse Meta
See the this page of tips and tricks for more details: Discourse New User Guide - users - Discourse Meta
@CC_Jon, No, we aren’t taken to the last reply we read. We’re randomly dumped into the middle of threads.
I’m finding that if I go to a thread that I have already caught up on since the migration, it will take me to the first unread post. But if it’s a thread that I haven’t looked at since the migration, it dumps me anywhere from the first post to somewhere in the middle. So I guess it’s working as it should now. I’m on a laptop using Windows/Chrome.
We’re making some fixes tonight to that feature. Please check tomorrow (Tuesday) and let us know if it works better for you!
It still takes me to the top of already read posts in some threads. Unfortunately it is one of the most active threads and it is a constant scrolling this morning, even though I read through the posts last night.
Can you help me track down the problem? When you go to the top of the thread, do you see a “Back” button on the timeline slider?
Do you notice if it’s the same threads that have the problem or is it more random than that?
It might also help to know what device you are using and what browser.
No “Back” button is displayed. I have played around with it on my laptop using Google Chrome as my browser and still the issue. I have to either slide the bar on most bookmarks to get to the most recent or unread posts, clicking on it does nothing, but I can also click on “Last reply” to take me down to the very bottom or most recent post and work my way back up that way. It’s definitely not opening up the bookmarked discussion and taking me to the beginning of unread posts.
UPDATE: Edit Not showing when I returned after typing this. 
And the back button finally showed up! I didn’t do anything different since I had a tab open. Clicked on a bookmark and could finally see it to click on
A post was merged into an existing topic: Unable to post messages earlier