Resources for learning Mandarin Chinese This is a community-maintained list of resources for learning Mandarin Chinese.
Alphabetical Index

Add-ons (browser)
Apps
Books
Dictionaries
Language Exchanges
Lists of Resources
News
Online Courses and Tutors
Podcasts
Social Media
Software
Textbooks
Websites

Just write in the appropriate answer/section. If you have concerns, questions, post a meta question, so we don't clutter the comments, but you can link your meta question from the comments.
Organization

Answers have a type of resource each.
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Add the resources in alphabetical order so they're easier to find.
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Browser Add-ons
General

Add Pinyin - Chinese Zero to Hero Reader (Chrome)

Chinese Tutor (Chrome: Flashcards, Speaking, Dictionary, Extension) is a flashcard extension.

Flixlingo (Chrome).

Language Learning with Netflix (Chrome).

Language Learning with YouTube (Chrome).

New Tong Wen Tang (Chrome; Firefox) converts between simplified and traditional Chinese.

Hanzisize (Chrome) enlarges Chinese text.


Popup dictionaries

Akkadu (Firefox)
Perapera Chinese (Firefox)
Frill (Safari)
GlotDojo (Chrome) with Chinese premium
Inkah (Chrome; Firefox)
LiuChan Chinese Popup Dictionary (Chrome; Firefox)
Popover Chinese (Safari)
Zhongwen: The Popular Chinese Learning Tool (Chrome; Firefox)
Zhongzhong: An improved Chinese Dictionary (Chrome)