diff --git a/Userland/Libraries/LibJS/Tests/builtins/RegExp/RegExp.prototype.exec.js b/Userland/Libraries/LibJS/Tests/builtins/RegExp/RegExp.prototype.exec.js
index 535bfa72680..f781a5bb3f8 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/RegExp/RegExp.prototype.exec.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/RegExp/RegExp.prototype.exec.js
@@ -127,3 +127,12 @@ test("non-greedy brace quantifier", () => {
     expect(res.length).toBe(1);
     expect(res[0]).toBe("abc");
 });
+
+// #6208
+test("brace quantifier with invalid contents", () => {
+    let re = /{{lit-746579221856449}}|<!--{{lit-746579221856449}}-->/;
+    let res = re.exec("{{lit-746579221856449}}");
+
+    expect(res.length).toBe(1);
+    expect(res[0]).toBe("{{lit-746579221856449}}");
+});
diff --git a/Userland/Libraries/LibRegex/RegexParser.cpp b/Userland/Libraries/LibRegex/RegexParser.cpp
index 54400f958b1..a331875a51e 100644
--- a/Userland/Libraries/LibRegex/RegexParser.cpp
+++ b/Userland/Libraries/LibRegex/RegexParser.cpp
@@ -880,7 +880,7 @@ StringView ECMA262Parser::read_digits_as_string(ReadDigitsInitialZeroState initi
     size_t offset = 0;
     auto start_token = m_parser_state.current_token;
     while (match(TokenType::Char)) {
-        auto c = m_parser_state.current_token.value();
+        auto& c = m_parser_state.current_token.value();
 
         if (follow_policy == ReadDigitFollowPolicy::DisallowNonDigit) {
             if (hex && !AK::StringUtils::convert_to_uint_from_hex(c).has_value())
@@ -892,6 +892,11 @@ StringView ECMA262Parser::read_digits_as_string(ReadDigitsInitialZeroState initi
         if (max_count > 0 && count >= max_count)
             break;
 
+        if (hex && !AK::StringUtils::convert_to_uint_from_hex(c).has_value())
+            break;
+        if (!hex && !c.to_uint().has_value())
+            break;
+
         offset += consume().value().length();
         ++count;
     }
@@ -933,31 +938,41 @@ bool ECMA262Parser::parse_quantifier(ByteCode& stack, size_t& match_length_minim
         repetition_mark = Repetition::Optional;
     } else if (match(TokenType::LeftCurly)) {
         consume();
+        auto chars_consumed = 1;
         repetition_mark = Repetition::Explicit;
 
-        auto low_bound = read_digits();
+        auto low_bound_string = read_digits_as_string();
+        chars_consumed += low_bound_string.length();
+
+        auto low_bound = low_bound_string.to_uint();
 
         if (!low_bound.has_value()) {
-            set_error(Error::InvalidBraceContent);
-            return false;
+            back(chars_consumed + 1);
+            return true;
         }
 
         repeat_min = low_bound.value();
 
         if (match(TokenType::Comma)) {
             consume();
-            auto high_bound = read_digits();
-            if (high_bound.has_value())
+            ++chars_consumed;
+            auto high_bound_string = read_digits_as_string();
+            auto high_bound = high_bound_string.to_uint();
+            if (high_bound.has_value()) {
                 repeat_max = high_bound.value();
+                chars_consumed += high_bound_string.length();
+            }
         } else {
             repeat_max = repeat_min;
         }
 
         if (!match(TokenType::RightCurly)) {
-            set_error(Error::MismatchingBrace);
-            return false;
+            back(chars_consumed + 1);
+            return true;
         }
+
         consume();
+        ++chars_consumed;
 
         if (repeat_max.has_value()) {
             if (repeat_min.value() > repeat_max.value())