YouTube Link Title

Adds video thumbnail on mouse hover and embeds video on click.

Play videos in-line without opening new tabs and scroll page at the same time.

Also supported: Invidious, Vimeo, LiveLeak, Dailymotion, vidme, WorldStarHipHop, Vine, Coub, Streamable.

This script is mostly functional.

YouTube titles are disabled for now but can be enabled.

Feel free to fork (but change the YouTube API key).

If you left-click a video link, the video gets embedded and started.

• Time offsets like "t=3m21s" are preserved.
• You can still follow links normally by middle click, Ctrl + click etc.
• Some uploaders don't want their videos to be embedded. These videos will open in a new tab.
• Embed modes:

1. inline (link gets replaced with video)
2. draggable, non-scrolling in-page popup (default)
3. freely resizable popup window (doesn't close when you leave the page)

Also:

• Support for Invidious (just invidious.osi.kr instance for now), Vimeo, LiveLeak, Dailymotion, vidme, WorldStarHipHop, Vine, Coub and Streamable
• Supports rComments for reddit for every comment load.
• Titles are cached to reduce traffic and delay on subsequent visits.
• To change settings: Monkey toolbar icon → "User Script Commands" → "Set up YouTube Link Title..."

What it does

• If link text doesn't contain a URL, the video title will be added as tooltip instead.
• A crossed out link indicates that the video is unavailable.
• Move cursor over links to see preview images.
• URLs are rewritten to clean HTTPS addresses.

Enable YouTube titles

• Just use a nice userscript like YouTube Peek Preview
• If you really want it enabled in this script, then:
• Uncomment lines 216, 217, and 219
• replace the API key on line 657: after "String.fromCharCode.apply". You can create one in Developer Console using instructions from here
• Before: net.json('https://www.googleapis.com/youtube/v3/videos?id=' + vid + '&part=' + part.join(',') + '&fields=items(' + fields.join(',') + ')&' + String.fromCharCode.apply(String, [107,101,121,61,65,73,122,97,83,121,68,87,120,79,114,52,76,105,52,65,54,72,116,89,120,57,107,55,98,86,98,67,81,54,56,118,112,119,74,74,117,111,99]), function(code, obj, txt) {
• After: net.json('https://www.googleapis.com/youtube/v3/videos?id=' + vid + '&part=' + part.join(',') + '&fields=items(' + fields.join(',') + ')&' + 'key=NEWYOUTUBEAPIKEYHERE', function(code, obj, txt) { where NEWYOUTUBEAPIKEYHERE is your own API Key

CSP problems

• Some embeds may fail to load with because of Content Security Policy:
• Content Security Policy can be carefully overidden to allow very specific embeds on chosen websites
• Use an extension like Content Security Policy Override very cautiously and at your own risk.

Todo

• Invidious: specify your own instances: single or multiple
• Invidious: option to redirect youtube to chosen invidious instance
• Invidious: edge cases with inv.domain/videoID (not inv.domain/watch?v=videoID)
• More sites: Tiktok?
• Combine with YouTube Peek Preview. Make thumbnail preview and titling better