diff --git a/src/editor/menu_project.lua b/src/editor/menu_project.lua
index f0bd5fe023..168af0038d 100644
--- a/src/editor/menu_project.lua
+++ b/src/editor/menu_project.lua
@@ -122,6 +122,7 @@ end
 
 function ProjectUpdateProjectDir(projdir,skiptree)
   local dir = wx.wxFileName.DirName(FixDir(projdir))
+  dir:Normalize() -- turn into absolute path if needed
   if not wx.wxDirExists(dir:GetFullPath()) then return end
 
   projdir = dir:GetPath(wx.wxPATH_GET_VOLUME) -- no trailing slash
diff --git a/src/editor/singleinstance.lua b/src/editor/singleinstance.lua
index 8eeeb2d146..46833a76e1 100644
--- a/src/editor/singleinstance.lua
+++ b/src/editor/singleinstance.lua
@@ -50,9 +50,7 @@ if success then -- ok, server was started, we are solo
           if filename then
             RequestAttention()
             if wx.wxDirExists(filename) then
-              local dir = wx.wxFileName.DirName(filename)
-              dir:Normalize() -- turn into absolute path if needed
-              ProjectUpdateProjectDir(dir:GetFullPath())
+              ProjectUpdateProjectDir(filename)
             elseif not ActivateFile(filename) then
               DisplayOutputLn(TR("Can't open file '%s': %s"):format(filename, wx.wxSysErrorMsg()))
             end
diff --git a/src/main.lua b/src/main.lua
index 5dba767fa9..3f7f3c4b71 100644
--- a/src/main.lua
+++ b/src/main.lua
@@ -553,9 +553,7 @@ do
   for _, filename in ipairs(filenames) do
     if filename ~= "--" then
       if wx.wxDirExists(filename) then
-        local dir = wx.wxFileName.DirName(filename)
-        dir:Normalize() -- turn into absolute path if needed
-        ProjectUpdateProjectDir(dir:GetFullPath())
+        ProjectUpdateProjectDir(filename)
       elseif not ActivateFile(filename) then
         DisplayOutputLn(("Can't open file '%s': %s"):format(filename, wx.wxSysErrorMsg()))
       end