"Open Folder..." fails for UNC path

[per1234]

Bug Description:

Attempting to open a folder from a network share fails silently.

Steps to Reproduce:

Set up

Create a network share:

1. Create two nested folders in any convenient location:

   foo/
   └── bar/
   

2. Right click on the foo folder.
3. Select "Properties" from the context menu.
4. Select the "Sharing" tab.
5. Click the "Share..." button.
6. Click the "Share" button.
7. Confirm the share in the Windows UAC prompt dialog.
8. Click the "Done" button on the "Your folder is shared" dialog.
9. Click the "Close" button on the "Properties" dialog.

Steps

1. Start the Theia "Electron example": https://github.com/eclipse-theia/theia/blob/master/doc/Developing.md#quick-start
2. Select File > Open Folder... from the example application's menus.
3. Select "Network" from the file tree in the navigation panel.
4. Open the machine that has the shared folder in the navigation panel.
5. Open the "foo" network share in the navigation panel.
6. Select the bar folder.
7. Click the "Select Folder" button.

🐛 A new window opens which does not have the bar folder loaded in the Explorer view.

Additional Information

• Operating System: Windows 10
• Theia Version: 4542e03

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The fault does not occur if I open the folder from the drive instead of from the network share.

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I can not reproduce the fault using VS Code.

[AlanGitMan]

I entered the text below as a new submission but was told to continue on here - as it seems like this issues has got lost in the cracks between Arduino and Eclipse - each one seems to be waiting for the other to do something......

The version of Eclipse-theia included in Arduino IDE V2.3.3 is - according to Arduino support - causing a highly reproducible issue with the use of UNC filenames when a Windows client and a Windows fileshare server are in use. I believe this is a known problem of quite long standing - please take this as a request to expedite a fix. .
Bug Description:

My config: Windows 10 22H2 Build 19045.5011 16GB RAM 3.2GHz Intel processor.
When Arduino IDE user opens an existing project which resides on a UNC network share like:
\windowserv\arduino\projects\myproject\myproject.ino

no error message is shown but the user only gets an empty template project. If the IDE is closed and restarted, then the project is correctly loaded. This affects any Arduino user who is using Windows to Windows file sharing using UNC. Arduino support says this is due to an issue with UNC filename handling in the Eclipse library.
Steps to Reproduce:

In Arduino V2.3.3 click on file->Open
Enter a UNC path like \\windowserv\arduino\projects\myproject\myproject.ino
Click "Open" button.
No error message occurs, but the user just gets a default empty project with just template "setup" and "loop" functions.
Close the Arduino IDE.
Open it up again - your project is NOW opened correctly.
The same thing happens if you click File-->preferences and set your default sketchbook location to a UNC share and open a project.
If you map the Arduino share to a local drive name (essentially mount the share as a drive letter) - for example map the share as drive "q:"
then open
q:\projects\myproject\myproject.ino"
then it all works as it should. This is not an ideal workaround for reasons given below.

Additional Information

This potentially affects any users of Arduino IDE on Windows (which is reckoned to be 70% of users) though in reality it is those using Arduino IDE in shared environments (home networks, schools, colleges, universities) who will be affected. As shown above, the mapped drives workaround is available, but that workaround comes with its own set of issues which arise from thread blocking in the client Windows system when network or hardware problems can occur - even if the shared drive is not actually in use. So the workaround is less than ideal.

Operating System: Windows 10 (probably 11 as well)
Theia Version: Whatever version is built into Arduino V2.3.3