I spawned in my world, I noticed a mountain was in front of me, and when I got a closer look, there was a big gap in the ground, showing the void. I have no idea how this happened,but I did notice that it took longer to load my word than usual (about 15-20 seconds longer). If there is any way to fix this, please comment below. I have provided some screenshots of what happened below.
UPDATE: \/
I explored around the mountain, and I noticed it did not split the world in half, but it was a large square of land (~300 x ~300 blocks). I noticed more chunks nearby it.
Thank you.
I don't think you understand what this site is for. You seem to be looking for interactive help from other players. That is not what the bug tracker is for. I think you're looking for Community Support.
The bug tracker is for reporting bugs, but just because something doesn't work the way you expect it to, doesn't mean you have a bug. Most of the time, it means you don't fully understand how a game mechanic works, or you've made a simple mistake, or something went wrong outside the game that caused the game to hiccup. Community Support can help you solve those kinds of problems, and you can also get answers to most questions about game mechanics on the Minecraft Wiki.
Normally, you should start your search for help on the Community Support Discord and/or the game wiki to make sure you understand what should be happening, but since we're already engaging about this I'll go ahead and start you out with the basic info they'll give you. First, based on your screenshots your world is clearly corrupted, and unless you've been regularly exporting copies you're not going to be able to recover it. (Exported copies can be re-imported to recover a world in the event that the world was damaged.) You might be able to use it as it is now by avoiding the damaged areas, but there's no guarantee that you can do this far into the future.
The damage might have been caused by a bug, but it probably wasn't or we've have many more reports of worlds with defects like these. Instead, it's more likely that the damage was initially the result of an external event such as a sudden loss of power on your computer, or opening your world in a third-party editing tool without fully understanding how to use it. Then, if you didn't notice or tried to disregard the initial damage, each time you played the world it probably accumulated more damage until finally it interfered with play. That sounds like where you are now. Sadly, by the time this happens there's been so much damage to the world that it's no longer possible to guess what started it, even if it was a bug.
In the future, I strongly recommend that you export worlds that are important to you after every session playing them. If possible, keep multiple of the most recent copies. Since you're using Windows 10, you should have File History, which can help by saving copies of each of your exported backups for as long as you let it, with no effort on your part (other than to do the export).
At this time I'm going to resolve this report ticket as Incomplete because you haven't described a bug or given us any hint about how to reproduce it. (Mojang can't fix a problem that they can's reproduce.) If you eventually decide that you can identify a bug that may have caused your problem, please create a new report following the format given in the Issue Guidelines linked below. Be prepared to wait a lot longer for action to be taken on your report, as it usually takes weeks and sometimes months or years to get a bug fixed.
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