The PiP Subtitle Enabler is a Firefox extension designed to improve the Picture-in-Picture (PiP) viewing experience by ensuring subtitles are visible. This tool activates soft subtitles within video elements, specifically targeting the elements that contain WebVTT formatted subtitles. By default, many websites do not set these tracks to 'showing', which is where this extension plays a crucial role. With it, users can enjoy videos with subtitles while multitasking, as the extension ensures that subtitles are always ready when PiP mode is activated.

However, it is important to note that the extension has limitations. It does not support JavaScript-rendered or WASM-rendered captions, which may affect its functionality on certain platforms like Crunchyroll. Additionally, it cannot create subtitles if none are available, and Firefox may impose restrictions on displaying captions in PiP mode on specific domains for privacy and security reasons. Overall, this extension is a valuable tool for users seeking to enhance their video viewing experience.