This can happen when Minecraft is unable to load a resource in a resource pack.
Try increasing your GUI Scale in Video Settings.
All of these mobs can be ridden by baby zombies
Adult chickens
Untamed ocelots
Untamed cats
Untamed wolves
Adult zombies
Adult husks
Adult zombie villagers
Adult zombified piglins
Cows
Adult unsaddled pigs
Sheep
Adult untamed horses
Adult untamed donkeys
Adult untamed mules
Adult skeleton horses
Adult zombie horses
Mooshrooms
Spiders that were not spawned as a jockey mount
Cave spiders
Pandas
2.0 was only meant to be released privately and was not intended to be given to the general public. 2.0 doesn’t show in the Launcher anyway.
Due to a change in how Minecraft downloads files, sounds for Alpha 1.1.2 and below can’t be downloaded.
English Only: Mojang only accepts bug reports in English; do not create bug reports in other languages. - Solo en inglés: Mojang solo acepta informes de errores en inglés; No cree informes de errores en otros idiomas.
General connection issues (Realms, Marketplace) and authentication issues are NOT bugs and are not allowed on the bug tracker
These issues are typically outside the control of the game’s code and are usually due to server maintenance, downtime, or local network configuration. For troubleshooting tips, see Troubleshoot Minecraft Network Connection Errors. - Los problemas generales de conexión (Realms, Marketplace) y los problemas de autenticación NO son errores y no están permitidos en el rastreador de errores
Estos problemas suelen estar fuera del control del código del juego y suelen deberse al mantenimiento del servidor, al tiempo de inactividad o a la configuración de la red local. Para obtener sugerencias para solucionar problemas, consulta Solucionar errores de conexión de red de Minecraft.
minecraft:generic-gravity Information: The gravity affecting an entity in blocks per tick squared. Default Value: 0.08
server.properties: allow-flight: Whether players can use flight on the server while in Survival mode by using mods.
With allow-flight enabled, griefers may become more common, because it makes their work easier. In Creative mode, this has no effect.
false - Flight is not allowed (players in air for at least 5 seconds get kicked).
true - Flight is allowed, and used if the player has a fly mod installed.
The server doesn't know if any attributes are affecting the player in any way, therefore causing the server to kick the player.
This is an Intended Feature as a Skulk Sensors have a 10 tick (0.5 second) cooldown period to prevent the sensor from reactivating when a contraption it is powering (such as a piston) becomes unpowered. The gif you provided shows the 10 tick delay when you were walking.
Any entity that Minecraft has to load causes performance issues. Since you are spawning so many, then Minecraft has to go ahead and render every single one.