YouTube's built-in subtitle editor doesn't support styling of any kind. If you want formatting such as bold, italic and coloring, you need to upload a subtitle file instead. The site accepts a number ...
Find the audioNameHash line and add the filename as it is written in the original file name (match if lower or uppercase): 1969 Dodge Charger R/T 426 Hemi V8 lgcy01chargerv8 Legacy_DMC 5MODS Link ️ 2 ...