diff --git a/javascript/edit-attention.js b/javascript/edit-attention.js
index 89b37aaf41a..ee48eb99cb6 100644
--- a/javascript/edit-attention.js
+++ b/javascript/edit-attention.js
@@ -71,16 +71,23 @@ function keyupEditAttention(event) {
         closeCharacter = '>';
         delta = opts.keyedit_precision_extra;
     } else if (selectionStart > 0 && /\(.*\)|\[.*\]/s.test(text.slice(selectionStart - 1, selectionEnd + 1))) {
-        closeCharacter = null;
-        if (isPlus) {
-            text = text.slice(0, selectionStart) + text[selectionStart - 1] + text.slice(selectionStart, selectionEnd) + text[selectionEnd] + text.slice(selectionEnd);
-            selectionStart++;
-            selectionEnd++;
+        let start = text[selectionStart - 1];
+        let end = text[selectionEnd];
+        let numParen = 0;
+
+        while (text[selectionStart - numParen - 1] == start && text[selectionEnd + numParen] == end) {
+            numParen++;
+        }
+
+        if (start == "(") {
+            weight = 1.1 ** numParen;
         } else {
-            text = text.slice(0, selectionStart - 1) + text.slice(selectionStart, selectionEnd) + text.slice(selectionEnd + 1);
-            selectionStart--;
-            selectionEnd--;
+            weight = 0.9 ** numParen;
         }
+
+        text = text.slice(0, selectionStart - numParen) + "(" + text.slice(selectionStart, selectionEnd) + ":" + weight + ")" + text.slice(selectionEnd + numParen);
+        selectionStart -= numParen - 1;
+        selectionEnd -= numParen - 1;
     } else if (selectionStart == 0 || !/\(.*:-?[\d.]+\)/s.test(text.slice(selectionStart - 1, selectionEnd + text.slice(selectionEnd).indexOf(")") + 1))) {
         // do not include spaces at the end
         while (selectionEnd > selectionStart && text[selectionEnd - 1] == ' ') {
@@ -97,23 +104,21 @@ function keyupEditAttention(event) {
         selectionEnd++;
     }
 
-    if (closeCharacter) {
-        var end = text.slice(selectionEnd + 1).indexOf(closeCharacter) + 1;
-        var weight = parseFloat(text.slice(selectionEnd + 1, selectionEnd + end));
-        if (isNaN(weight)) return;
-
-        weight += isPlus ? delta : -delta;
-        weight = parseFloat(weight.toPrecision(12));
-        if (String(weight).length == 1) weight += ".0";
-
-        if (closeCharacter == ')' && weight == 1) {
-            var endParenPos = text.substring(selectionEnd).indexOf(')');
-            text = text.slice(0, selectionStart - 1) + text.slice(selectionStart, selectionEnd) + text.slice(selectionEnd + endParenPos + 1);
-            selectionStart--;
-            selectionEnd--;
-        } else {
-            text = text.slice(0, selectionEnd + 1) + weight + text.slice(selectionEnd + end);
-        }
+    var end = text.slice(selectionEnd + 1).indexOf(closeCharacter) + 1;
+    var weight = parseFloat(text.slice(selectionEnd + 1, selectionEnd + end));
+    if (isNaN(weight)) return;
+
+    weight += isPlus ? delta : -delta;
+    weight = parseFloat(weight.toPrecision(12));
+    if (Number.isInteger(weight)) weight += ".0";
+
+    if (closeCharacter == ')' && weight == 1) {
+        var endParenPos = text.substring(selectionEnd).indexOf(')');
+        text = text.slice(0, selectionStart - 1) + text.slice(selectionStart, selectionEnd) + text.slice(selectionEnd + endParenPos + 1);
+        selectionStart--;
+        selectionEnd--;
+    } else {
+        text = text.slice(0, selectionEnd + 1) + weight + text.slice(selectionEnd + end);
     }
 
     target.focus();