FDLIST (conferences in algebra etc.)

RepresentationTheory.ca (more conferences)

W.A.R.T.H.O.G. summer school (Ben Elias and Nick Proudfoot's summer school. I attended in graduate school.)

Sydney's Informal Friday Seminar

Northeastern Geometry, Physics, and Representation Theory seminar

MIT Lie groups seminar

MIT infinite dimensional algebra seminar

Yale Geometry, Physics, and Symmetry seminar

Yale Quantum Topology and Field Theory seminar

Berkeley Informal String-Math seminar

AIM Online Research Community on Link Homology

Seminar on Modular and Geometric Rep Theory (IAS Fall 2020)

Sydney Mathematical Research Institute Youtube Channel (Notes for Geordie's course on the youtube channel can be found here.)

Virtual Rep Theory Seminar

Categorification at Home

MSRI summer school on Soergel bimodules (There is a book based off these lectures. I coauthored a section on "Lefschetz Linear Algebra".)

MSRI summer school on planar algebras

MSRI summer school on Graphical models in algebraic combinatorics

Notes from the Dacha seminar (Juteau, Mautner, Riche, and Williamson on modular geometric representation theory.)

Videos from the QUACKS conference. (Includes an excellent minicourse by You Qi on categorification at a root of unity.) 

GKM and Equivariant Schubert Calculus

Goncharov IHES lectures (Quantum Geometry of Moduli Spaces of Local Systems and Representation Theory)

Kamnitzer CRM lecture 1, 2, 3 (Webs and skew Howe duality)