diff --git a/internal/cmd/config.go b/internal/cmd/config.go
index 1cb2ce08ed6..606cf611c90 100644
--- a/internal/cmd/config.go
+++ b/internal/cmd/config.go
@@ -2783,8 +2783,16 @@ func (f *ConfigFile) toMap() map[string]any {
 		configFile.Diff.Pager = ""
 	}
 
+	// This is a horrible hack. We want the returned map to contain only simple
+	// types because they are used with masterminds/sprig template functions
+	// which don't accept fmt.Stringers in place of strings. As a work-around,
+	// round-trip via JSON.
+	data, err := json.Marshal(configFile)
+	if err != nil {
+		return nil
+	}
 	var result map[string]any
-	if err := mapstructure.Decode(configFile, &result); err != nil {
+	if err := json.Unmarshal(data, &result); err != nil {
 		panic(err)
 	}
 	return result
diff --git a/internal/cmd/testdata/scripts/addautotemplate.txtar b/internal/cmd/testdata/scripts/addautotemplate.txtar
index e7b477c42e8..24095e0a67c 100644
--- a/internal/cmd/testdata/scripts/addautotemplate.txtar
+++ b/internal/cmd/testdata/scripts/addautotemplate.txtar
@@ -8,15 +8,15 @@ exec chezmoi add --autotemplate $HOME${/}.symlink
 cmp $CHEZMOISOURCEDIR/symlink_dot_symlink.tmpl golden/symlink_dot_symlink.tmpl
 
 # test that chezmoi add --autotemplate does not create a template if no replacements occurred
-exec chezmoi add --autotemplate $HOME${/}.file
-cmp $CHEZMOISOURCEDIR/dot_file golden/dot_file
+exec chezmoi add --autotemplate $HOME${/}.notatemplate
+cmp $CHEZMOISOURCEDIR/dot_notatemplate golden/dot_notatemplate
 
 # test that chezmoi add --autotemplate escapes brackets
 exec chezmoi add --autotemplate $HOME${/}.vimrc
 cmp $CHEZMOISOURCEDIR/dot_vimrc.tmpl golden/dot_vimrc.tmpl
 
--- golden/dot_file --
-# contents of .file
+-- golden/dot_notatemplate --
+# contents of .notatemplate
 -- golden/dot_template.tmpl --
 key = {{ .variable }}
 -- golden/dot_vimrc.tmpl --
@@ -26,8 +26,8 @@ set foldmarker={{ "{{" }},{{ "}}" }}
 -- home/user/.config/chezmoi/chezmoi.toml --
 [data]
     variable = "value"
--- home/user/.file --
-# contents of .file
+-- home/user/.notatemplate --
+# contents of .notatemplate
 -- home/user/.template --
 key = value
 -- home/user/.vimrc --
diff --git a/internal/cmd/testdata/scripts/issue3602.txtar b/internal/cmd/testdata/scripts/issue3602.txtar
new file mode 100644
index 00000000000..1d1d7df77bd
--- /dev/null
+++ b/internal/cmd/testdata/scripts/issue3602.txtar
@@ -0,0 +1,2 @@
+# test that the .chezmoi.config.destDir template variable is compatible with the replace template function
+exec chezmoi execute-template '{{ .chezmoi.config.destDir | replace "abc" "def "}}'