diff --git a/vendor/profile.ps1 b/vendor/profile.ps1
index 0394209..fc0f324 100644
--- a/vendor/profile.ps1
+++ b/vendor/profile.ps1
@@ -155,9 +155,14 @@ Set-Item -Path function:\PrePrompt   -Value $PrePrompt   -Options Constant
 Set-Item -Path function:\CmderPrompt -Value $CmderPrompt -Options Constant
 Set-Item -Path function:\PostPrompt  -Value $PostPrompt  -Options Constant
 
+<#
+This scriptblock runs every time the prompt is returned.
+Explicitly use functions from MS namespace to protect from being overridden in the user session.
+Custom prompt functions are loaded in as constants to get the same behaviour
+#>
 [ScriptBlock]$Prompt = {
     $realLASTEXITCODE = $LASTEXITCODE
-    $host.UI.RawUI.WindowTitle = Split-Path $pwd.ProviderPath -Leaf
+    $host.UI.RawUI.WindowTitle = Microsoft.PowerShell.Management\Split-Path $pwd.ProviderPath -Leaf
     PrePrompt | Microsoft.PowerShell.Utility\Write-Host -NoNewline
     CmderPrompt
     Microsoft.PowerShell.Utility\Write-Host "`nλ " -NoNewLine -ForegroundColor "DarkGray"
@@ -166,5 +171,6 @@ Set-Item -Path function:\PostPrompt  -Value $PostPrompt  -Options Constant
     return " "
 }
 
+# Functions can be made constant only at creation time
 # ReadOnly at least requires `-force` to be overwritten
 Set-Item -Path function:\prompt  -Value $Prompt  -Options ReadOnly