How to show all messages in threads where unread exist

[Eric S Fraga]

Hello,
Probably it's silly question, but I didn't find the answer in the Gnus
documentation. How to show all messages in threads, where unread
messages exist?

I don't think it's easy to show all messages in threads but you can
easily show all those that are direct predecessors in the thread.

"A T" at the summary may do what you want or part thereof.

You might also wish to look at

,----[ C-h v gnus-fetch-old-headers RET ]
| gnus-fetch-old-headers is a variable defined in `gnus-sum.el'.
| Its value is t
| Original value was nil
|
| Documentation:
| *Non-nil means that Gnus will try to build threads by grabbing old headers.
| If an unread article in the group refers to an older, already
| read (or just marked as read) article, the old article will not
| normally be displayed in the Summary buffer. If this variable is
| t, Gnus will attempt to grab the headers to the old articles, and
| thereby build complete threads. If it has the value `some', all
| old headers will be fetched but only enough headers to connect
| otherwise loose threads will be displayed. This variable can
| also be a number. In that case, no more than that number of old
| headers will be fetched. If it has the value `invisible', all
| old headers will be fetched, but none will be displayed.
|
| The server has to support NOV for any of this to work.
|
| This feature can seriously impact performance it ignores all
| locally cached header entries. Setting it to t for groups for a
| server that doesn't expire articles (such as news.gmane.org),
| leads to very slow summary generation.
|
| You can customize this variable.
|
| [back]
`----