diff --git a/timetagger/app/dialogs.py b/timetagger/app/dialogs.py
index 6a69dd8..147189e 100644
--- a/timetagger/app/dialogs.py
+++ b/timetagger/app/dialogs.py
@@ -1687,11 +1687,23 @@ def open(self, mode, record, callback=None):
                 el.innerText = x
                 self.maindiv.appendChild(el)
 
+        # Keep track of composing state (e.g. entering JCK characters) to avoid prematurely submitting on enter (#594)
+        self._is_composing = False
+        self._ds_input.addEventListener(
+            "compositionstart", lambda: self._set_compose_state(True)
+        )
+        self._ds_input.addEventListener(
+            "compositionend", lambda: self._set_compose_state(False)
+        )
+
         # Almost done. Focus on ds if this looks like desktop; it's anoying on mobile
         super().open(callback)
         if utils.looks_like_desktop():
             self._ds_input.focus()
 
+    def _set_compose_state(self, value):
+        self._is_composing = value
+
     def _autocomp_finished(self):
         self._show_tags_from_ds()
         self._mark_as_edited()
@@ -1854,6 +1866,8 @@ def _on_key(self, e):
         if self._autocompleter.on_key(e):
             e.stopPropagation()
             return
+        elif self._is_composing:
+            pass
         elif key == "enter" or key == "return":
             self.submit_soon()
         else:
@@ -2406,10 +2420,22 @@ def open(self, tags, callback=None):
 
         self._records = []
 
+        # Keep track of composing state (e.g. entering JCK characters)
+        self._is_composing = False
+        self._tagname2.addEventListener(
+            "compositionstart", lambda: self._set_compose_state(True)
+        )
+        self._tagname2.addEventListener(
+            "compositionend", lambda: self._set_compose_state(False)
+        )
+
         super().open(callback)
         if utils.looks_like_desktop():
             self._tagname2.focus()
 
+    def _set_compose_state(self, value):
+        self._is_composing = value
+
     def close(self):
         self._records = []
         super().close()
@@ -2428,6 +2454,8 @@ def _on_name2_done(self):
 
     def _on_key2(self, e):
         key = e.key.lower()
+        if self._is_composing:
+            pass
         if key == "enter" or key == "return":
             e.stopPropagation()
             e.preventDefault()
@@ -2578,6 +2606,18 @@ def open(self):
         if utils.looks_like_desktop():
             self._search_input.focus()
 
+        # Keep track of composing state (e.g. entering JCK characters)
+        self._is_composing = False
+        self._search_input.addEventListener(
+            "compositionstart", lambda: self._set_compose_state(True)
+        )
+        self._search_input.addEventListener(
+            "compositionend", lambda: self._set_compose_state(False)
+        )
+
+    def _set_compose_state(self, value):
+        self._is_composing = value
+
     def close(self):
         self._autocompleter.close()
         self._records = []
@@ -2654,6 +2694,8 @@ def _on_key(self, e):
         if self._autocompleter.on_key(e):
             e.stopPropagation()
             return
+        elif self._is_composing:
+            pass
         elif key == "enter" or key == "return":
             e.stopPropagation()
             e.preventDefault()