diff --git a/lib/rules_inline/state_inline.mjs b/lib/rules_inline/state_inline.mjs
index d1c00a6..8d33819 100644
--- a/lib/rules_inline/state_inline.mjs
+++ b/lib/rules_inline/state_inline.mjs
@@ -118,9 +118,8 @@ StateInline.prototype.scanDelims = function (start, canSplitWord) {
   function getLastCharCode (str, pos) {
     // treat beginning of the line as a whitespace
     if (pos <= 0) { return 0x20 }
-    const charCode = str.codePointAt(pos - 1)
+    const charCode = str.charCodeAt(pos - 1)
     // not low surrogates (BMP)
-    // undefined & 0xFC00 = 0, but never happens thanks to the first if
     if ((charCode & 0xFC00) !== 0xDC00) { return charCode }
 
     // undefined if out of range (leading stray low surrogates)