This is probably a bug and the mojang will need to fix the  launcher, but I suggest making a backup of your saves folder, deleting .minecraft and the launcher, and reinstalling.

If you continue to have problems with the regular launcher, feel free to use MultiMC (multimc.org)

Minecraft Launcher NOT launching any Previous Versions!

Hardrocker

LordGeek101

Minecraft: Java Edition

Ravalle

ContraVz

Cube1337x

_akira0810

iceball8314

1.2.1

1.2.2

1.2.3

1.2.4

1.2.5

1.3.1

1.3.2

1.4.2

1.4.4

1.4.5

1.4.6

1.4.7

1.5.1

1.5.2

1.6.1

1.6.2

1.6.4

1.7.2

1.7.4

1.7.5

1.7.9

1.7.10

1.8.1 Easy

Normal

Hard

Hardcore

1.8.2

1.8.3

1.8.4

1.8.5

1.8.6

1.8.7

1.8.8 4 Players

5-9 Players

10+ Players

1.8.9

1.7.6

1.7.7

1.7.8

1.9.1

1.9.2

1.9.3

1.9.4

1.10

1.11.2

1.11

1.12

1.12.1

1.12.2 2 Players

3 Players

1.7.3 Set Seed

Random Seed

1.0-1.6

1.8-1.11

No F3

1.13

1.13.1

1.13.2

1.10.2

1.14

1.14.2

1.14.3

1.14.4

1.15

1.15.1

1.15.2 Pre 1.8

1.13-1.15

Pre 1.9

1.14+

1.9-1.15

Vanilla

Version

Difficulty

Players

Seed Type (Any% Glitchless)

Version Range (AA)

Seed Type (Any%)

Seed Type

Seed Type (Any% Glitchless Peaceful)

Seed Type (AA)

Version Range (AAdv)

Seed Type (AAdv)

Version Range (Any% Glitchless)

Version Range (Any%)

Version Range (Any% RSG Co-op)

Mods

Version Range (Any% Glitchless (Peaceful))

Version Range (Any% (Peaceful))

Version Range (Any% Glitchless (Demo))

Player Count (AAdv Co-op)

Seed/Glitch (AAdv Co-op)

Version Range (AAdv Co-op)

Seed Type (Combined Any%)

Seed Type (Any% Time Travel)

Seed type (Any% Glitchless Co-op)

Splits (Combined Any%)

**Updated Legal Mods:**

• AntiResourceReload 4.0.2 for 1.14-1.15.2 is now allowed, which fixes a crash when loading the mod outside of a development environment.

• StandardSettings 1.2.3 for 1.14-1.19.2 is now allowed. This update adds an f3PauseOnWorldLoad option that, when enabled and pauseO

StandardSettings & AntiResourceReload

New and Obsolete Mods

Updated Mod Rules

Minecraft

Minecraft Speedrunning Questions Thread

Form for requesting custom map / server leaderboards

Ninjabrain bot doesnt show up on top

Help ! FSG Seed Generator Doesnt Work !

how do you get atum and speedrunigt for 1.12

Speedrun Wall on MAC

Awesomecuber

AprilSR

skylewl

draconix

nwolc

Luminosity

Bloon

ElRichi

DrGuy

Keima

nottherealben

Winrar

DraquoDrass

Specnr

AlEmeralds

Armpitsmoothie

audioSalix

gaylea

BSRF

luvvlyjude

EvanKeen

taffel

Hayley

tildejustin

drip120

the_yuukster

r0hkx

Leonn

leto_saa

Olock5

mariofan65

MooMooRuns

Deadpool

DaBias2

fox4869