diff --git a/libs/remix-solidity/src/compiler/compiler-utils.ts b/libs/remix-solidity/src/compiler/compiler-utils.ts
index da3bc487b3..7e19ae7d8a 100644
--- a/libs/remix-solidity/src/compiler/compiler-utils.ts
+++ b/libs/remix-solidity/src/compiler/compiler-utils.ts
@@ -12,9 +12,21 @@ export const pathToURL = {}
  * @param version is the version of compiler with or without 'soljson-v' prefix and .js postfix
  */
 export function urlFromVersion (version) {
-  if (!version.startsWith('soljson-v')) version = 'soljson-v' + version
-  if (!version.endsWith('.js')) version = version + '.js'
-  return `${pathToURL[version]}/${version}`
+  let url
+  if (version === 'builtin') {
+    let location: string | Location = window.document.location
+    let path = location.pathname
+    if (!path.startsWith('/')) path = '/' + path
+    location = `${location.protocol}//${location.host}${path}assets/js`
+    if (location.endsWith('index.html')) location = location.substring(0, location.length - 10)
+    if (!location.endsWith('/')) location += '/'
+    url = `${location}soljson.js`
+  } else {
+    if (!version.startsWith('soljson-v')) version = 'soljson-v' + version
+    if (!version.endsWith('.js')) version = version + '.js'
+    url = `${pathToURL[version]}/${version}`
+  }
+  return url
 }
 
 /**
diff --git a/libs/remix-ui/solidity-compiler/src/lib/compiler-container.tsx b/libs/remix-ui/solidity-compiler/src/lib/compiler-container.tsx
index 9469121adf..80b1004ab6 100644
--- a/libs/remix-ui/solidity-compiler/src/lib/compiler-container.tsx
+++ b/libs/remix-ui/solidity-compiler/src/lib/compiler-container.tsx
@@ -333,19 +333,15 @@ export const CompilerContainer = (props: CompilerContainerProps) => {
       updateCurrentVersion(selectedVersion)
       url = customUrl
       api.setParameters({ version: selectedVersion })
-    } else if (selectedVersion === 'builtin') {
-      let location: string | Location = window.document.location
-      let path = location.pathname
-      if (!path.startsWith('/')) path = '/' + path
-      location = `${location.protocol}//${location.host}${path}assets/js`
-      if (location.endsWith('index.html')) location = location.substring(0, location.length - 10)
-      if (!location.endsWith('/')) location += '/'
-      url = location + 'soljson.js'
     } else {
-      if (selectedVersion.indexOf('soljson') !== 0 || helper.checkSpecialChars(selectedVersion)) {
-        return console.log('loading ' + selectedVersion + ' not allowed')
+      if (helper.checkSpecialChars(selectedVersion)) {
+        return console.log('loading ' + selectedVersion + ' not allowed, special chars not allowed.')
+      }
+      if (selectedVersion === 'builtin' || selectedVersion.indexOf('soljson') === 0) {
+        url = urlFromVersion(selectedVersion)
+      } else {
+        return console.log('loading ' + selectedVersion + ' not allowed, version should start with "soljson"')
       }
-      url = `${urlFromVersion(selectedVersion)}`
     }
 
     // Workers cannot load js on "file:"-URLs and we get a