firefox: make undo work.

* firefox/jp-hash.js (jp_hash_edit): Use execCommand
to issue insertText actions to edit the object,
rather than doing it directly, so that undo integrity
is preserved.

1 files changed, 8 insertions, 6 deletions

diff --git a/firefox/jp-hash.js b/firefox/jp-hash.js
index 4e76e99..f23ba46 100644
--- a/firefox/jp-hash.js
+++ b/firefox/jp-hash.js
@@ -105,17 +105,19 @@ async function jp_hash_edit(elem)
 
     if (start != end) {
       let len = elem.value.length;
-      let head = elem.value.substring(0, start);
       let sel = elem.value.substring(start, end);
-      let tail = elem.value.substring(end, len);
 
       jphash(sel, (jph) => {
-                    elem.value = head + jph + tail;
-                    elem.selectionStart = start;
-                    elem.selectionEnd = start + jph.length;
+                    elem.focus();
+                    document.execCommand("insertText", false, jph);
+                    elem.setSelectionRange(start, start + jph.length);
                   });
     } else {
-      jphash(elem.value, (jph) => { elem.value = jph; });
+      jphash(elem.value, (jph) => {
+                           elem.focus();
+                           elem.select();
+                           document.execCommand("insertText", false, jph);
+                         });
     }
   }
 }