diff --git a/config.example.toml b/config.example.toml
index 598b0ff..c4ebd65 100644
--- a/config.example.toml
+++ b/config.example.toml
@@ -6,6 +6,7 @@ url = "https://matrix.org"
 
 [settings]
 default_room = "#iamb-users:0x.badd.cafe"
+external_edit_file_suffix = ".md"
 log_level = "warn"
 message_shortcode_display = false
 open_command = ["my-open", "--file"]
diff --git a/docs/iamb.5 b/docs/iamb.5
index 48c5412..90d86de 100644
--- a/docs/iamb.5
+++ b/docs/iamb.5
@@ -125,6 +125,9 @@ key and can be overridden as described in
 .Sx PROFILES .
 .Bl -tag -width Ds
 
+.It Sy external_edit_file_suffix
+Suffix to append to temporary file names when using the :editor command. Defaults to .md.
+
 .It Sy default_room
 The room to show by default instead of the
 .Sy :welcome
diff --git a/src/config.rs b/src/config.rs
index 6d7dd0e..4d31fff 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -507,6 +507,7 @@ pub struct TunableValues {
     pub notifications: Notifications,
     pub image_preview: Option<ImagePreviewValues>,
     pub user_gutter_width: usize,
+    pub external_edit_file_suffix: String,
 }
 
 #[derive(Clone, Default, Deserialize)]
@@ -530,6 +531,7 @@ pub struct Tunables {
     pub notifications: Option<Notifications>,
     pub image_preview: Option<ImagePreview>,
     pub user_gutter_width: Option<usize>,
+    pub external_edit_file_suffix: Option<String>,
 }
 
 impl Tunables {
@@ -557,6 +559,9 @@ impl Tunables {
             notifications: self.notifications.or(other.notifications),
             image_preview: self.image_preview.or(other.image_preview),
             user_gutter_width: self.user_gutter_width.or(other.user_gutter_width),
+            external_edit_file_suffix: self
+                .external_edit_file_suffix
+                .or(other.external_edit_file_suffix),
         }
     }
 
@@ -580,6 +585,9 @@ impl Tunables {
             notifications: self.notifications.unwrap_or_default(),
             image_preview: self.image_preview.map(ImagePreview::values),
             user_gutter_width: self.user_gutter_width.unwrap_or(30),
+            external_edit_file_suffix: self
+                .external_edit_file_suffix
+                .unwrap_or_else(|| ".md".to_string()),
         }
     }
 }
diff --git a/src/tests.rs b/src/tests.rs
index 4d4de21..b385992 100644
--- a/src/tests.rs
+++ b/src/tests.rs
@@ -186,6 +186,7 @@ pub fn mock_tunables() -> TunableValues {
         .into_iter()
         .collect::<HashMap<_, _>>(),
         open_command: None,
+        external_edit_file_suffix: String::from(".md"),
         username_display: UserDisplayStyle::Username,
         message_user_color: false,
         notifications: Notifications {
diff --git a/src/windows/room/chat.rs b/src/windows/room/chat.rs
index 8f42d72..3a74e93 100644
--- a/src/windows/room/chat.rs
+++ b/src/windows/room/chat.rs
@@ -5,7 +5,8 @@ use std::fs;
 use std::ops::Deref;
 use std::path::{Path, PathBuf};
 
-use edit::edit as external_edit;
+use edit::edit_with_builder as external_edit;
+use edit::Builder;
 use modalkit::editing::store::RegisterError;
 use std::process::Command;
 use tokio;
@@ -481,7 +482,9 @@ impl ChatState {
                 let msg = self.tbox.get();
 
                 let msg = if let SendAction::SubmitFromEditor = act {
-                    external_edit(msg.trim_end().to_string())?
+                    let suffix =
+                        store.application.settings.tunables.external_edit_file_suffix.as_str();
+                    external_edit(msg.trim_end().to_string(), Builder::new().suffix(suffix))?
                 } else if msg.is_blank() {
                     return Ok(None);
                 } else {