I'm working on moving over from Lightroom to DigiKam. One thing I can't seem to figure out is how to see the count of a particular tag, within a particular "Album" (which seems to be digiKam's name for a folder).

What I tried:
1) Settings->Configure digiKam->Views->Tree-Views->Show a count of items in Tree Views=checked
2) In the main UI, to to Tumbnails view
3) Under the "Albums" tab on the left, highlight an album. The main view now shows the photos in that album, as expected. Let's say there are 10 photos.
4) Under Filters->Tags Filter (on the right), each tag still shows the counts for each tag in the entire collection. For example, even though there are only 10 photos, some tags may show 500 (since there are 500 total photos with that tag).
5) Captions->Tags (on the right) behaves the same: it doesn't show just the counts of tags in the current view, but the counts of tags throughout the entire collection.

The corresponding UI in Lightroom shows counts corresponding to the current view. I cannot seem to find any way in digiKam to do the same...?

Settings > Configure > Tree View font: > Show a count of items in Tree Views = ON

I stated that option in step 1 of my original post. Please see the remaining steps.

Hello metal450,
yes, I have seen it, and I have tried it on myself: Exactly with this method the counter of albums and tags appears or disappears. (My system is Manjaro Linux).

Here's a screencast showing the behavior: https://jiij.cc/snaps/2023-01-28_13.51.28.mp4

You're saying yours doesn't behave like this? When you switch albums, the tag counts shown on the right change to only reflect the number of those tags in the selected albums? The counts don't always remain the same, as in this screencast and as described in my original post?

Hello metal450,
oh, I was too quick and didn't quite understand your question at first. I thought you were just asking where to set the number of tags and albums to be displayed.
If you want to know how many tags are in an album - unfortunately I don't know.
I can only say: if you click on the bottom left, next to Search... click on: Tags "already assingnet", then only the already assigned tags are displayed for the respective image. I use that often.
I'm sorry that I can't help you.