How to use sort title?

[JackyHe398]

May i know what is the default sort title for a directory? As description in this (https://forum.jellyfin.org/t-solved-seas...0#pid53230) threads, there are 5 directories under the show(named "Season 01", "Season 02", "Season 03", "OAD", "Visions of Coleus"). When I named the sort title of 2 special season to  '"Season 01.5"' and  '"Season 02.5"' (with double quote), it correctly goes to the very beginning of the season section. but when i named them without a double quote, they will simply stay at the end ("Season 01", "Season 02", "Season 03", "OAD", "Visions of Coleus") instead of going to the middle  ("Season 01" , "OAD", "Season 02" , "Visions of Coleus" , "Season 03"). It only works properly when I give all the Season a sort title. 

May i know what is the default sort title? Is it the name of the directory, the title or there is no default sort title? (Also I would like to mention that there are no information about sort title when i search in documentation.)

[Efficient_Good_5784]

It works alphabetically & numerically. If an item doesn't have a sort title, the regular title will be used to sort.

So titles will be sorted based on alphabetical order.
Just give all folders a sort title starting with a number to get the order you want them to be displayed as.

[TheDreadPirate]

Keep in mind that Jellyfin relies on your file naming and organization matching your preferred metadata source (TMDB by default). The way you are trying to name your folders is fighting against what Jellyfin expects and needs to work automatically.

Ideally, what you should be doing is putting all your Specials in a "Specials" folder. Some times TMDB/TVDB/AniDB will automatically pull down metadata for placing a special before or after the regular season episodes. If it doesn't you can manually edit the specials to specify what episode they will appear before/after.

[JackyHe398]

Keep in mind that Jellyfin relies on your file naming and organization matching your preferred metadata source (TMDB by default).  The way you are trying to name your folders is fighting against what Jellyfin expects and needs to work automatically.

Ideally, what you should be doing is putting all your Specials in a "Specials" folder.  Some times TMDB/TVDB/AniDB will automatically pull down metadata for placing a special before or after the regular season episodes.  If it doesn't you can manually edit the specials to specify what episode they will appear before/after.

Since I am dealing with 転生したらスライムだった件(That Time I Got Reincarnated as a Slime), and they really separated those SPs to different seasons, I will stick to how I catergorize it(mainly because it work just fine so i want it to stay organized). 

It works alphabetically & numerically. If an item doesn't have a sort title, the regular title will be used to sort.

So titles will be sorted based on alphabetical order.
Just give all folders a sort title starting with a number to get the order you want them to be displayed as.

Now my file structure is like this. where "第 xx 季" means "Season xx". Now I've tried to name OADs and 柯里烏斯之夢(Visions of Coleus) to  "第 1.5 季" and "第 2.5 季". 

but as you see, they're not in the right place. As I've tried in terminal, if the title of Season 1-3 is taken as what it shown as "第 xx 季", it should work perfectly.

user@truenas:~/temp$ ls
'第 1 季'  '第 1.5 季'  '第 2 季'  '第 2.5 季'

That's why i am so confused. It cannot work either i name them in the display language or english.