I'm providing the vtt file & the converted srt file in the below zip please help me & see if you can fix the problem!
subtitles.zip

& I got the vtt subtitle from this youtube video https://www.youtube.com/watch?v=f61KMw5zVhg

It appears that in a segmented VTT the timestamp is indicated by the MPEGTS value, which is offset by 1 second (90000). The correct start time (in seconds) could therefore be calculated by dividing the MPEG-TS by 90000, less one. Elgindy-VTT-to-SRT-Subtitle-Converter seems to use the local time, which in a segmented WebVTT is always zero.

WEBVTT
X-TIMESTAMP-MAP=MPEGTS:900000,LOCAL:00:00:00.000

WEBVTT
X-TIMESTAMP-MAP=MPEGTS:13204800,LOCAL:00:00:00.000

1
00:00:00.000 --> 00:00:03.440
<i>First Sentence.</i>

WEBVTT
X-TIMESTAMP-MAP=MPEGTS:13514400,LOCAL:00:00:00.000

2
00:00:01.480 --> 00:00:03.560
<i>Second Sentence.</i>

Actually the only useful VTT to SRT converter that works like expected.

However I use batch files to download videos from youtube with subtitles into one folder, so the "Select folder" is a good catch. Yet everytime I start the program, I need to browse my drives again to select the right folder.

Could it be possible to keep the last settings ? Or the last 3 settings in a combo box ? For instance :

1: Files | list of files
2: Folder | Selected folder
3: Folder | Selected another folder

Btw, Happy New Year

Hello developer,i got this message

can you enable long path directory support for this apps

The spesific path, file name, or both are too long. the fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters.

See the end of this message for details on invoking
just-in-time (JIT) debugging instead of this dialog box.

************** Exception Text **************
System.IO.PathTooLongException: The specified path, file name, or both are too long. The fully qualified file name must be less than 260 characters, and the directory name must be less than 248 characters.
at System.IO.PathHelper.GetFullPathName()
at System.IO.Path.LegacyNormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
at System.IO.Path.NormalizePath(String path, Boolean fullCheck, Int32 maxPathLength, Boolean expandShortPaths)
at System.IO.Path.GetFullPathInternal(String path)
at Elgindy_VTT_to_SRT_Converter.Form1.Eo3aREiZtBJo6Rbvmc(Object )
at Elgindy_VTT_to_SRT_Converter.Form1.WpgK41SyY(Object , EventArgs )
at System.Windows.Forms.Control.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnClick(EventArgs e)
at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ButtonBase.WndProc(Message& m)
at System.Windows.Forms.Button.WndProc(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

************** Loaded Assemblies **************
mscorlib
Assembly Version: 4.0.0.0
Win32 Version: 4.8.4042.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/Windows/Microsoft.NET/Framework/v4.0.30319/mscorlib.dll

Elgindy VTT to SRT Converter
Assembly Version: 1.0.0.0
Win32 Version: 1.2.0.0
CodeBase: file:///C:/Users/defaultuser0/Downloads/Elgindy.VTT.to.SRT.Converter.exe

System
Assembly Version: 4.0.0.0
Win32 Version: 4.8.4001.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System/v4.0_4.0.0.0__b77a5c561934e089/System.dll

System.Windows.Forms
Assembly Version: 4.0.0.0
Win32 Version: 4.8.4042.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Windows.Forms/v4.0_4.0.0.0__b77a5c561934e089/System.Windows.Forms.dll

System.Drawing
Assembly Version: 4.0.0.0
Win32 Version: 4.8.3752.0 built by: NET48REL1
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Drawing/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Drawing.dll

System.Configuration
Assembly Version: 4.0.0.0
Win32 Version: 4.8.3752.0 built by: NET48REL1
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Configuration/v4.0_4.0.0.0__b03f5f7f11d50a3a/System.Configuration.dll

System.Core
Assembly Version: 4.0.0.0
Win32 Version: 4.8.4042.0 built by: NET48REL1LAST_C
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Core/v4.0_4.0.0.0__b77a5c561934e089/System.Core.dll

System.Xml
Assembly Version: 4.0.0.0
Win32 Version: 4.8.3752.0 built by: NET48REL1
CodeBase: file:///C:/WINDOWS/Microsoft.Net/assembly/GAC_MSIL/System.Xml/v4.0_4.0.0.0__b77a5c561934e089/System.Xml.dll

************** JIT Debugging **************
To enable just-in-time (JIT) debugging, the .config file for this
application or computer (machine.config) must have the
jitDebugging value set in the system.windows.forms section.
The application must also be compiled with debugging
enabled.

For example:

When JIT debugging is enabled, any unhandled exception
will be sent to the JIT debugger registered on the computer
rather than be handled by this dialog box.

https://www.virustotal.com/gui/file/d73a6cc55ca2bb767f990a6e5fefe5f661a8d8e9041ac15dc561797e847781ea/detection

Thank you for creating a very useful application.

I have a problem with the difference in the results of the conversion.
Where if I use an online converter, the result will add two 00 numbers at the beginning and can be read by the media player.
While the results of this application he did not add two 00 at the beginning.

This is from online converter

This from your app

converted vtt file contains text format in srt output

source file
https://gist.github.com/darodi/3ff8be373302fcd8c8bb0f9069dc7208#file-je-suis-la-2853734-fra-vtt

target file
https://gist.github.com/darodi/3ff8be373302fcd8c8bb0f9069dc7208#file-je-suis-la-2853734-fra-srt

as you can see,

1
00:00:07,120 --> 00:00:09,480 
<c.magenta.bg_black>Musique douce</c>

insead of

1
00:00:07,120 --> 00:00:09,480 
Musique douce

This is not a real issue but why do that need the Admin privileges.
Please remove them and i hope i can see a drag n drop support.
Thanks for the great jop.