Subtitle on Disable ?!

[eltodesukane]

Subtitle on Disable by default when video playing, Sub Track has to be selected manually, but MKVToolNix GUI shows the ass track is the Default track.
Why? How to fix?
(I want to attach a video, but how?)
(I am using VLC 3.0.11 on Windows 10 desktop computer)

[Hitchhiker]

Provided subtitles are enabled in Preferences they will play automatically along with the video. To check hit Ctrl + P and click the Subtitles / OSD button. If "Enable subtitles" is already checkmarked click the big Reset Preferences button at the bottom. Save, exit and restart vlc.

To view all the shortcut keys for subtitles click the Hotkeys button in Preferences, type subtitle (without the 's') in the search field and they'll be displayed in the pane below.

As regards your question about attaching a video that's not possible on the forum. But you can upload a short clip to Zippyshare and then post the link to it here, or upload it to youtube.com or some other video hosting site.