200714 2019-08-14 07:36:27 -0700 String.prototype.replace truncates $<number> values 2019-08-19 01:18:27 -0700 1 1 1 Unclassified WebKit JavaScriptCore Safari 12 All All RESOLVED INVALID InRadar P2 Normal --- 1 matt webkit-unassigned fpizlo matt msaboff webkit-bug-importer oldest_to_newest 1561148 0 matt 2019-08-14 07:36:27 -0700 # Summary When replacing with a value that contains $<number>, the value is truncated of $ and first number. # Test var string = "Get %{amount} credit"; var regex = new RegExp(`%{amount}`, "g"); console.log(string.replace(regex, "$100")); # Expected > Get $100 credit # Actual > Get 00 credit 1561150 1 matt 2019-08-14 07:39:08 -0700 This could be related to a non-standard feature: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/n#Examples 1561202 2 webkit-bug-importer 2019-08-14 09:59:13 -0700 <rdar://problem/54306164> 1562679 3 matt 2019-08-19 01:18:27 -0700 After further investigation, this issue looks to be caused by an old String.prototype.replace polyfill from core-js@2.0.3. Ref: https://github.com/zloirock/core-js/blob/v2.0.3/modules/es6.regexp.replace.js