Issue 6507 - Inject style sheet proactively from background page

include.preload.js

Index: include.preload.js
===================================================================
--- a/include.preload.js
+++ b/include.preload.js
@@ -495,52 +495,54 @@
       browser.runtime.sendMessage({
         type: "devtools.traceElemHide",
         selectors: [],
         filters
       });
     }
   },
 
-  apply()
+  apply({trace, inline, inlineEmulated, selectors, emulatedPatterns} = {})
   {
-    browser.runtime.sendMessage({type: "elemhide.getSelectors"}, response =>
-    {
-      if (this.tracer)
-        this.tracer.disconnect();
-      this.tracer = null;
+    if (this.tracer)
+      this.tracer.disconnect();
+    this.tracer = null;
 
-      if (response.trace)
-        this.tracer = new ElementHidingTracer();
+    if (trace)
+      this.tracer = new ElementHidingTracer();
 
-      this.inline = response.inline;
-      this.inlineEmulated = !!response.inlineEmulated;
+    this.inline = inline;
+    this.inlineEmulated = !!inlineEmulated;
 
-      if (this.inline)
-        this.addSelectorsInline(response.selectors, "standard");
+    if (this.inline)
+      this.addSelectorsInline(selectors, "standard");
 
-      if (this.tracer)
-        this.tracer.addSelectors(response.selectors);
+    if (this.tracer)
+      this.tracer.addSelectors(selectors);
 
-      // Prefer CSS selectors for -abp-has and -abp-contains unless the
-      // background page has asked us to use inline styles.
-      this.elemHideEmulation.useInlineStyles = this.inline ||
-                                               this.inlineEmulated;
+    // Prefer CSS selectors for -abp-has and -abp-contains unless the
+    // background page has asked us to use inline styles.
+    this.elemHideEmulation.useInlineStyles = this.inline ||
+                                             this.inlineEmulated;
 
-      this.elemHideEmulation.apply(response.emulatedPatterns);
-    });
+    this.elemHideEmulation.apply(emulatedPatterns);
   }
 };
 
 if (document instanceof HTMLDocument)
 {
   checkSitekey();
 
   elemhide = new ElemHide();
-  elemhide.apply();
+
+  browser.runtime.onMessage.addListener(message =>
+  {
+    if (message.type == "elemhide.apply")
+      elemhide.apply(message);
+  });
 
   document.addEventListener("error", event =>
   {
     checkCollapse(event.target);
   }, true);
 
   document.addEventListener("load", event =>
   {