Broken Heirarchy in 2018.1.6f1

I realize this isn't a support thread, I'm more of just trying to raise awareness/see if this is a well-known issue.
According to Unity's Issue Tracker, this issue was resolved several years ago, though obviously not if I'm experiencing it now.
Trying to rename anything in the hierarchy makes the whole tab's text dissappear and is no longer editable. Upon mouse motion through the hierarchy or trying to rename anything, I'm given a nullreference exception in UnityEditor.ToolTipView.Close(). Here's a copy of the error:

Code (CSharp):

1. NullReferenceException: Object reference not set to an instance of an object
2. UnityEditor.TooltipView.Close () (at C:/buildslave/unity/build/Editor/Mono/TooltipView/TooltipView.cs:94)
3. UnityEditor.RenameOverlay.RemoveMessage () (at C:/buildslave/unity/build/Editor/Mono/GUI/RenameOverlay.cs:335)
4. UnityEditor.RenameOverlay.EndRename (Boolean acceptChanges) (at C:/buildslave/unity/build/Editor/Mono/GUI/RenameOverlay.cs:111)
5. UnityEditor.IMGUI.Controls.TreeViewController.EndNameEditing (Boolean acceptChanges) (at C:/buildslave/unity/build/Editor/Mono/GUI/TreeView/TreeViewController.cs:821)
6. UnityEditor.SceneHierarchyWindow.OnLostFocus () (at C:/buildslave/unity/build/Editor/Mono/SceneHierarchyWindow.cs:416)
7. System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)
8. Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
9. System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:232)
10. System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MethodBase.cs:115)
11. UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:291)
12. UnityEditor.HostView.Invoke (System.String methodName) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:284)
13. UnityEditor.HostView.OnLostFocus () (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:131)

I've tried uninstalling, reinstalling, and upgrading Unity to the newest version to no avail. If anyone has any suggestions if this is a unique case, I'm open to any suggestions. Thanks for your time.

 

An update: it seems Unity's tooltip is entirely broken, though I'm not sure what to do about it. A forum post addressing a similar issue suggested resetting Unity's layout, (top right corner). However, my issue is that the tooltip, for whatever reason, isn't being referenced at all, and as such, I'm actually given another error upon trying to reset to Unity default: failed to destroy window #1, which in this case, is the hierarchy view.

 

I assume you mean 2018.1f6, yea?

Moving to correct forum.

 

Yes, thank you. Updated title as well.

 

Another update: per a second forum post I read, I tried renaming the project file, which seemed to work. I will post if this solves my issue or if I experience degraded performance again.

 

If you know how to reproduce the issue, please submit a bug-report to allow Unity Technologies to fix this issue.
https://unity3d.com/unity/qa/bug-reporting

If you can't do that for whatever reason, please let us know how to reproduce this issue, so someone else could send a report.

 

Unfortunately, I have absolutely no idea why this happened so it'll be a longshot as to trying to reproduce it.
However, I did manage to solve the problem (supposedly, as it hasn't happened again) by renaming my project folder.

 

Thank you so much! You saved my day with this quote!
This worked for me!