SOLVED: [EDIT] [10.11.1] update - No chapters anymore in movies/series episodes

[ClémentXVII]

[EDIT thanks to serlmercant, I realised that actually movies that were uploaded before 10.11.1 also lost their chapters]
Is anyone else unable to have chapters show up in their library since the 10.11.1 update? Any idea where I should look for more information?

Chapters were working great before the update.
All my files are extracted from the original discs using MakeMKV.
Chapters seem to have gone from the files uploaded before 10.11.1 
====
Before update 10.11.1: chapters available on all library

• Movies : chapters available and I could jump ahead or backwards
  
• Series episodes:
  

1. chapters available and I could jump ahead or backwards with a curved arrow pointing forwards/backwards
   
2. I could also skip to the next/ previous episodes with the ">|" or "|<" straight arrows
   

After update 10.11.1 (any client: Windows/Linux/Mac/Web/Android)
Chapters available on all library uploaded _AFTER_ the change to 10.11.1
No Chapters available at all on library items uploaded _BEFORE_ the change to 10.11.1

• Movies : chapters available and I can still jump ahead or backwards
  
• Series episodes:
  

1. chapters not available and I cannot jump ahead or backwards (no curved arrow pointing forwards/backwards in the interface, nor chapter lines in the timeline)
   
2. I can still skip to the next/ previous episodes with the ">|" or "|<" straight arrows
   

[serlmercant]

Since updating I have had the same issue with my entire collection; no chapter markers in movies or tv shows. The only exception is for media I've added to my collection after the update. Chapter markers are still present and functional when opening the source files in VLC.

[ClémentXVII]

Oh you're right! I just checked with movies I had uploaded earlier and indeed, there I also have the "no chapters" issue.

I'll update the title of my post to reflect this.

[ClémentXVII]

Since updating I have had the same issue with my entire collection; no chapter markers in movies or tv shows. The only exception is for media I've added to my collection after the update. Chapter markers are still present and functional when opening the source files in VLC.

So your reply made me think on how files may be handled by JellyFin.
And I selected one series episode to refresh the metadata -> "Refresh all metadata".
This enabled the chapter marks to return to that episode.

[SOLUTION]
If your movies/episodes have lost their chapters after a migration, perform the following:

For all your libraries, select "Refresh metadata -> refresh all metadata".
I didn't have to replace images.