My guess is if you have say blocks from biome mods removed either they disappear or the game tries to fill in gaps where it can. It's best to not remove mods that make major changes to the game (or add any if you wanting to change things later). It can ruin the experience and crash the game I'm pretty sure making the world unstable (mostly it crashes after too many mods are removed that do alter the game).
If you want to keep your mods and play in your friend's world. Just use a different profile. If your friend's world is in Vanilla (so unmodified) just create/select an unmodified profile from the installations tab in the launcher. It doesn't ruin anything and it's easy to do. I do this sometimes to play with other players on a server that have datapacks I play with sometimes and keep the modified profiles for when I want to use mods.
As you can see I have many modified versions, and the release/snapshot profiles (those appear by default though, but if I wanted to create another one I can just go to 'Installations' and select say 1.15.2 if I don't want to use 1.16.4 as the 'Latest' profiles stick to the latest version available so it's best to create a new one).
If you want to keep your mods and play in your friend's world. Just use a different profile. If your friend's world is in Vanilla (so unmodified) just create/select an unmodified profile from the installations tab in the launcher. It doesn't ruin anything and it's easy to do. I do this sometimes to play with other players on a server that have datapacks I play with sometimes and keep the modified profiles for when I want to use mods.
I want to add that it is vital to also change the game directory - far too many people have issues ranging from keybinds/settings being reset to unusual bugs to outright crashes to corrupted worlds when they run multiple versions, modded or vanilla, in the same directory, especially when the versions differ a lot (downgrading by even a single version is enough to wreck a world, as in a complete reset of loaded chunks, not just some missing blocks and items). This also makes it easy to manage multiple modded instances as each directory will have its own "mods" folder.
Also, while I have no experience with "modern" mods (Forge, Fabric, etc) my understanding is that they automatically assign IDs to blocks and items, which may be lost if you remove the mods (that is to say, the configurations, not the items in the world, assuming you didn't load it without mods), then reconfigured differently the next time you install them (I believe that worlds themselves should store the exact IDs used but things can always go wrong when removing/re-adding mods).
Good point. I was mostly just going off of if they are using just 1 version modded and switching between them but otherwise if they are using multiple or want better control/less conflicts then yes that would be the best approach. Don't know why I didn't add that part along with the other but oh well. XD
I don't think much has changed for removing content if you remove mods from 1.6.4 to 1.16.4 and regardless of modloaders (though I know of the 1.13+ ID change) the IDs I don't know how assigning them is effected in modern versions, but the contents from the mods still disappears completely and may or may not replace it (I can only go off when I remove mods after reviewing them not when changing mods in a modpack or accessing a world as my recent reference). Not really something I have much experience with or looked at in depth.
When I try to remove mods from the mod file in minecraft, and put them back in, the world goes weird (all blocks face the same way)
I only removed them to join a friend's world.
Any help would be awesome
Thanks
My guess is if you have say blocks from biome mods removed either they disappear or the game tries to fill in gaps where it can. It's best to not remove mods that make major changes to the game (or add any if you wanting to change things later). It can ruin the experience and crash the game I'm pretty sure making the world unstable (mostly it crashes after too many mods are removed that do alter the game).
If you want to keep your mods and play in your friend's world. Just use a different profile. If your friend's world is in Vanilla (so unmodified) just create/select an unmodified profile from the installations tab in the launcher. It doesn't ruin anything and it's easy to do. I do this sometimes to play with other players on a server that have datapacks I play with sometimes and keep the modified profiles for when I want to use mods.
As you can see I have many modified versions, and the release/snapshot profiles (those appear by default though, but if I wanted to create another one I can just go to 'Installations' and select say 1.15.2 if I don't want to use 1.16.4 as the 'Latest' profiles stick to the latest version available so it's best to create a new one).
Niche Community Content Finder, Youtuber, Modpack/Map Maker, Duck
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Wikis I Maintain: https://modwiki.miraheze.org/wiki/User:SuntannedDuck2
I want to add that it is vital to also change the game directory - far too many people have issues ranging from keybinds/settings being reset to unusual bugs to outright crashes to corrupted worlds when they run multiple versions, modded or vanilla, in the same directory, especially when the versions differ a lot (downgrading by even a single version is enough to wreck a world, as in a complete reset of loaded chunks, not just some missing blocks and items). This also makes it easy to manage multiple modded instances as each directory will have its own "mods" folder.
https://minecraft.gamepedia.com/Minecraft_launcher#Installations
Also, while I have no experience with "modern" mods (Forge, Fabric, etc) my understanding is that they automatically assign IDs to blocks and items, which may be lost if you remove the mods (that is to say, the configurations, not the items in the world, assuming you didn't load it without mods), then reconfigured differently the next time you install them (I believe that worlds themselves should store the exact IDs used but things can always go wrong when removing/re-adding mods).
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Good point. I was mostly just going off of if they are using just 1 version modded and switching between them but otherwise if they are using multiple or want better control/less conflicts then yes that would be the best approach. Don't know why I didn't add that part along with the other but oh well. XD
I don't think much has changed for removing content if you remove mods from 1.6.4 to 1.16.4 and regardless of modloaders (though I know of the 1.13+ ID change) the IDs I don't know how assigning them is effected in modern versions, but the contents from the mods still disappears completely and may or may not replace it (I can only go off when I remove mods after reviewing them not when changing mods in a modpack or accessing a world as my recent reference). Not really something I have much experience with or looked at in depth.
Niche Community Content Finder, Youtuber, Modpack/Map Maker, Duck
Forum Thread Maintainer for APortingCore, Liteloader Download HUB, Asphodel Meadows, Fabric Project, Legacy Fabric/Cursed Fabric, Power API, Rift/Fabric/Forge 1.13 to 1.17.
Wikis I Maintain: https://modwiki.miraheze.org/wiki/User:SuntannedDuck2