diff --git a/Dalamud/Plugin/Internal/PluginManager.cs b/Dalamud/Plugin/Internal/PluginManager.cs
index 2865d4f4d..6f1ffdb04 100644
--- a/Dalamud/Plugin/Internal/PluginManager.cs
+++ b/Dalamud/Plugin/Internal/PluginManager.cs
@@ -556,7 +556,12 @@ internal partial class PluginManager : IDisposable, IServiceType
     public async Task ReloadPluginMastersAsync(bool notify = true)
     {
         Log.Information("Now reloading all PluginMasters...");
-        await Task.WhenAll(this.Repos.Select(repo => repo.ReloadPluginMasterAsync()));
+
+        Debug.Assert(!this.Repos.First().IsThirdParty, "First repository should be main repository");
+        await this.Repos.First().ReloadPluginMasterAsync(); // Load official repo first
+
+        await Task.WhenAll(this.Repos.Skip(1).Select(repo => repo.ReloadPluginMasterAsync()));
+
         Log.Information("PluginMasters reloaded, now refiltering...");
 
         this.RefilterPluginMasters(notify);
@@ -730,6 +735,13 @@ internal partial class PluginManager : IDisposable, IServiceType
         // Reload as a local manifest, add some attributes, and save again.
         var manifest = LocalPluginManifest.Load(manifestFile);
 
+        if (manifest.InternalName != repoManifest.InternalName)
+        {
+            Directory.Delete(outputDir.FullName, true);
+            throw new Exception(
+                $"Distributed internal name does not match repo internal name: {manifest.InternalName} - {repoManifest.InternalName}");
+        }
+
         if (useTesting)
         {
             manifest.Testing = true;
diff --git a/Dalamud/Plugin/Internal/Types/PluginRepository.cs b/Dalamud/Plugin/Internal/Types/PluginRepository.cs
index 5c7659d90..e0373ff33 100644
--- a/Dalamud/Plugin/Internal/Types/PluginRepository.cs
+++ b/Dalamud/Plugin/Internal/Types/PluginRepository.cs
@@ -1,6 +1,8 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
+using System.Diagnostics;
+using System.Linq;
 using System.Net.Http;
 using System.Net.Http.Headers;
 using System.Threading.Tasks;
@@ -108,6 +110,35 @@ internal class PluginRepository
                 manifest.SourceRepo = this;
             }
 
+            var pm = Service<PluginManager>.Get();
+            var official = pm.Repos.First();
+            Debug.Assert(!official.IsThirdParty, "First repository should be official repository");
+
+            if (official.State == PluginRepositoryState.Success && this.IsThirdParty)
+            {
+                pluginMaster = pluginMaster.Where(thisRepoEntry =>
+                {
+                    if (official.PluginMaster!.Any(officialRepoEntry =>
+                                                       string.Equals(thisRepoEntry.InternalName, officialRepoEntry.InternalName, StringComparison.InvariantCultureIgnoreCase)))
+                    {
+                        Log.Warning(
+                            "The repository {RepoName} tried to replace the plugin {PluginName}, which is already installed through the official repo - this is no longer allowed for security reasons. " +
+                            "Please reach out if you have an use case for this.",
+                            this.PluginMasterUrl,
+                            thisRepoEntry.InternalName);
+                        return false;
+                    }
+
+                    return true;
+                }).ToList();
+            }
+            else if (this.IsThirdParty)
+            {
+                Log.Warning("Official repository not loaded - couldn't check for overrides!");
+                this.State = PluginRepositoryState.Fail;
+                return;
+            }
+
             this.PluginMaster = pluginMaster.AsReadOnly();
 
             Log.Information($"Successfully fetched repo: {this.PluginMasterUrl}");