the workaround I found was to force a reload when you collapse. it's real heavy handed, but I haven't had the time to dig in deeper.

index d12ca3d..3914c4b 100644
--- a/dired.py
+++ b/dired.py
@@ -582,6 +582,7 @@ class DiredFold(TextCommand, DiredBaseCommand):
     Very important, in case of actual modification of view, set valid dired_index setting
                     see DiredRefreshCommand docs for details
     '''
+
     def run(self, edit, update=None, index=None):
         '''
         update
@@ -698,6 +699,7 @@ class DiredFold(TextCommand, DiredBaseCommand):
         v.erase(edit, indented_region)
         v.set_read_only(True)
         emit_event(u'fold', (self.view.id(), self.index[start_line - 1]), view=self.view)
+        v.run_command('dired_refresh')


 class DiredUpCommand(TextCommand, DiredBaseCommand):

Why is this still needed in Sublime 4... I would ditch all other editors if they simply made the sidebar at least capable of switching sides...

I believe this bug is fixed in gwenzek's fork of this repo. Working great for me.

I was also getting disappearing entries when I press the left arrow key. The gwenzek fork fixes this for me.

Why is this still needed in Sublime 4... I would ditch all other editors if they simply made the sidebar at least capable of switching sides...

This is still better (faster) if you like to do everything by keyboard.

I believe this bug is fixed in gwenzek's fork of this repo. Working great for me.

I was also getting disappearing entries when I press the left arrow key. The gwenzek fork fixes this for me.

I tried installing the fork but that didnt work for me, error saying cannot iterate over None object. I downloaded the zip file from repo and renamed it with FileBrowser.sublime-package and added it in my Packages folder.
Is that how fork installation of package is done ?

i just did git -clone in terminal, in the packages/user directory.

git -clone https://github.com/gwenzek/SublimeFileBrowser.git

i still run into the same collapse of the folder . so i just combine dired_floder/dired_expand and dired_refresh this two command , it work fine for me. here is the example:

{
        "keys": ["h"], 
        "command": "chain", 
        "args":
        {
            "commands":[
            ["dired_fold",], 
            ["dired_refresh",], 
        ], 
        }, 
        "context": [
            { "key": "selector", "operator": "equal", "operand": "text.dired" },
            { "key": "setting.dired_rename_mode", "operand": false } 
        ], 
    },

and use this chian command need install chain of command in (st2 or st3),
as of st4 you can use that directly.

Fix is in #165