in a group chat, there was only one picture posted that day, (under the label "Today" as shown in the first screenshot) but in the gallery (all media) two images are shown under the header "today" one of them was from yesterday and isn't shown in the "yesterday" section (see the second screenshot)
chat view:

all media:

could you add the info boxes for both messages? (I need to see the date headers at which it was send and received)
This has most likely to do with the way ConversationActivity and Gallery/Media handle dates. iirc. ConversationActivity shows the stuff in the way the are send (more or less) and Gallery/Media the way they are received.
will do, it is happening again for other two pictures
this screenshots are all from 2 new pictures, the messages details are NOT from the old ones:
today pic:

yesterday pic is shown under today header:

today pic is info:

yesterday pic is info:

Thanks! I will investigate this more, Pic Info helped.
Problem is somewhere here:
org/thoughtcrime/securesms/database/loaders/BucketedThreadMediaLoader.java:88
Okay, now I have it figured out:
"Today" means "Last 24 hours"
"Yesterday" is the 24 hours before that
"This week" means "In the last 7*24 hours until yesterday"
"This month" is the same for 30 days.
I have to think about this.
i would not change the wording, this is just fine. but we can define
"this month" being (from today) 13. Jan to 13. Feb is a bit weird.
Most helpful comment
i would not change the wording, this is just fine. but we can define
and so on.
"this month" being (from today) 13. Jan to 13. Feb is a bit weird.