Update styletag injection to use <style> for platforms other than firefox (#508)

* update styletag injection to use <style> for platforms other than firefox

* lint

* specify HTMLStyleElement

Co-authored-by: Jonathan Kingston <[email protected]>

* fix typo

---------

Co-authored-by: Jonathan Kingston <[email protected]>

Author: dharb

src/utils.js

@@ -23,16 +23,25 @@ export function getInjectionElement () {
     return document.head || document.documentElement
 }
 
+// Tests don't define this variable so fallback to behave like chrome
+const hasMozProxies = typeof mozProxies !== 'undefined' ? mozProxies : false
+
 /**
  * Creates a script element with the given code to avoid Firefox CSP restrictions.
  * @param {string} css
- * @returns {HTMLLinkElement}
+ * @returns {HTMLLinkElement | HTMLStyleElement}
  */
 export function createStyleElement (css) {
-    const style = document.createElement('link')
-    style.href = 'data:text/css,' + encodeURIComponent(css)
-    style.setAttribute('rel', 'stylesheet')
-    style.setAttribute('type', 'text/css')
+    let style
+    if (hasMozProxies) {
+        style = document.createElement('link')
+        style.href = 'data:text/css,' + encodeURIComponent(css)
+        style.setAttribute('rel', 'stylesheet')
+        style.setAttribute('type', 'text/css')
+    } else {
+        style = document.createElement('style')
+        style.innerText = css
+    }
     return style
 }
 
@@ -53,9 +62,6 @@ export function setGlobal (globalObjIn) {
     Error = globalObj.Error
 }
 
-// Tests don't define this variable so fallback to behave like chrome
-const hasMozProxies = typeof mozProxies !== 'undefined' ? mozProxies : false
-
 // linear feedback shift register to find a random approximation
 export function nextRandom (v) {
     return Math.abs((v >> 1) | (((v << 62) ^ (v << 61)) & (~(~0 << 63) << 62)))