diff --git a/druid-shell/src/backend/gtk/application.rs b/druid-shell/src/backend/gtk/application.rs
index 1678f48e08..d6d615b3be 100644
--- a/druid-shell/src/backend/gtk/application.rs
+++ b/druid-shell/src/backend/gtk/application.rs
@@ -78,10 +78,20 @@ impl Application {
     }
 
     pub fn clipboard(&self) -> Clipboard {
-        Clipboard
+        Clipboard {
+            selection: gdk::SELECTION_CLIPBOARD,
+        }
     }
 
     pub fn get_locale() -> String {
         glib::get_language_names()[0].as_str().into()
     }
 }
+
+impl crate::platform::linux::LinuxApplicationExt for crate::Application {
+    fn primary_clipboard(&self) -> crate::Clipboard {
+        crate::Clipboard(Clipboard {
+            selection: gdk::SELECTION_PRIMARY,
+        })
+    }
+}
diff --git a/druid-shell/src/backend/gtk/clipboard.rs b/druid-shell/src/backend/gtk/clipboard.rs
index e4eaa01e63..3b084d5f8b 100644
--- a/druid-shell/src/backend/gtk/clipboard.rs
+++ b/druid-shell/src/backend/gtk/clipboard.rs
@@ -28,8 +28,21 @@ const CLIPBOARD_TARGETS: [&str; 5] = [
 ];
 
 /// The system clipboard.
-#[derive(Debug, Clone)]
-pub struct Clipboard;
+#[derive(Clone)]
+pub struct Clipboard {
+    pub(crate) selection: Atom,
+}
+
+impl std::fmt::Debug for Clipboard {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let name = match self.selection {
+            gdk::SELECTION_PRIMARY => "Primary",
+            gdk::SELECTION_CLIPBOARD => "Clipboard",
+            _ => "(other)",
+        };
+        f.debug_tuple("Clipboard").field(&name).finish()
+    }
+}
 
 impl Clipboard {
     /// Put a string onto the system clipboard.
@@ -37,7 +50,7 @@ impl Clipboard {
         let string = string.as_ref().to_string();
 
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
 
         let targets: Vec<TargetEntry> = CLIPBOARD_TARGETS
             .iter()
@@ -55,7 +68,7 @@ impl Clipboard {
     pub fn put_formats(&mut self, formats: &[ClipboardFormat]) {
         let entries = make_entries(formats);
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
         // this is gross: we need to reclone all the data in formats in order
         // to move it into the closure. :/
         let formats = formats.to_owned();
@@ -83,7 +96,7 @@ impl Clipboard {
     /// Get a string from the system clipboard, if one is available.
     pub fn get_string(&self) -> Option<String> {
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
 
         for target in &CLIPBOARD_TARGETS {
             let atom = Atom::intern(target);
@@ -99,7 +112,7 @@ impl Clipboard {
     /// highest priority on the system clipboard, or `None` if no types are supported.
     pub fn preferred_format(&self, formats: &[FormatId]) -> Option<FormatId> {
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
         let targets = clipboard.wait_for_targets()?;
         let format_atoms = formats
             .iter()
@@ -119,7 +132,7 @@ impl Clipboard {
     /// [`Clipboard::preferred_format`]
     pub fn get_format(&self, format: FormatId) -> Option<Vec<u8>> {
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
         let atom = Atom::intern(format);
         clipboard
             .wait_for_contents(&atom)
@@ -128,7 +141,7 @@ impl Clipboard {
 
     pub fn available_type_names(&self) -> Vec<String> {
         let display = gdk::Display::get_default().unwrap();
-        let clipboard = gtk::Clipboard::get_default(&display).unwrap();
+        let clipboard = gtk::Clipboard::get_for_display(&display, &self.selection);
         let targets = clipboard.wait_for_targets().unwrap_or_default();
         targets
             .iter()
diff --git a/druid-shell/src/clipboard.rs b/druid-shell/src/clipboard.rs
index 486234bcd6..ab992824c4 100644
--- a/druid-shell/src/clipboard.rs
+++ b/druid-shell/src/clipboard.rs
@@ -126,7 +126,7 @@ pub use crate::backend::clipboard as backend;
 /// [MIME types]: https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types
 /// [`ClipboardFormat`]: struct.ClipboardFormat.html
 #[derive(Debug, Clone)]
-pub struct Clipboard(backend::Clipboard);
+pub struct Clipboard(pub(crate) backend::Clipboard);
 
 impl Clipboard {
     /// Put a string onto the system clipboard.
diff --git a/druid-shell/src/platform/linux.rs b/druid-shell/src/platform/linux.rs
index fa8dbd0dcd..5e4071c076 100644
--- a/druid-shell/src/platform/linux.rs
+++ b/druid-shell/src/platform/linux.rs
@@ -24,3 +24,15 @@ pub trait LinuxApplicationExt {
     /// This is useful for middle mouse paste.
     fn primary_clipboard(&self) -> Clipboard;
 }
+
+#[cfg(test)]
+#[allow(unused_imports)]
+mod test {
+    use crate::Application;
+
+    use super::*;
+    use static_assertions as sa;
+    // TODO(shell/x11): implement LinuxApplicationExt
+    #[cfg(not(feature = "x11"))]
+    sa::assert_impl_all!(Application: LinuxApplicationExt);
+}