Make the imposter element tracked using TextSourceRange

ext/fg/js/document.js

@@ -70,12 +70,6 @@ function docImposterCreate(element) {
     return imposter;
 }
 
-function docImposterDestroy() {
-    for (const element of document.getElementsByClassName('yomichan-imposter')) {
-        element.parentNode.removeChild(element);
-    }
-}
-
 function docRangeFromPoint(point) {
     const element = document.elementFromPoint(point.x, point.y);
     let imposter = null;
@@ -92,12 +86,18 @@ function docRangeFromPoint(point) {
     }
 
     const range = document.caretRangeFromPoint(point.x, point.y);
+    if (range !== null && isPointInRange(point, range)) {
         if (imposter !== null) {
             imposter.style.zIndex = -2147483646;
             imposter.style.pointerEvents = 'none';
         }
-
-    return range !== null && isPointInRange(point, range) ? new TextSourceRange(range) : null;
+        return new TextSourceRange(range, '', imposter);
+    } else {
+        if (imposter !== null) {
+            imposter.parentNode.removeChild(imposter);
+        }
+        return null;
+    }
 }
 
 function docSentenceExtract(source, extent) {

ext/fg/js/frontend.js

@@ -307,10 +307,11 @@ class Frontend {
                 this.onError(e);
             }
         } finally {
+            if (textSource !== null) {
+                textSource.cleanup();
+            }
             if (hideResults && this.options.scanning.autoHideResults) {
                 this.searchClear();
-            } else {
-                docImposterDestroy();
             }
 
             this.pendingLookup = false;
@@ -371,7 +372,6 @@ class Frontend {
     }
 
     searchClear() {
-        docImposterDestroy();
         this.popup.hide();
         this.popup.clearAutoPlayTimer();
 

ext/fg/js/source.js

@@ -25,13 +25,20 @@ const IGNORE_TEXT_PATTERN = /\u200c/;
  */
 
 class TextSourceRange {
-    constructor(range, content='') {
+    constructor(range, content, imposter) {
         this.range = range;
         this.content = content;
+        this.imposter = imposter;
     }
 
     clone() {
-        return new TextSourceRange(this.range.cloneRange(), this.content);
+        return new TextSourceRange(this.range.cloneRange(), this.content, this.imposter);
+    }
+
+    cleanup() {
+        if (this.imposter !== null && this.imposter.parentNode !== null) {
+            this.imposter.parentNode.removeChild(this.imposter);
+        }
     }
 
     text() {
@@ -221,6 +228,10 @@ class TextSourceElement {
         return new TextSourceElement(this.element, this.content);
     }
 
+    cleanup() {
+        // NOP
+    }
+
     text() {
         return this.content;
     }

ext/mixed/js/display.js

@@ -84,16 +84,22 @@ class Display {
             if (textSource === null) {
                 return false;
             }
+
+            let definitions, length, sentence;
+            try {
                 textSource.setEndOffset(this.options.scanning.length);
 
-            const {definitions, length} = await apiTermsFind(textSource.text());
+                ({definitions, length} = await apiTermsFind(textSource.text()));
                 if (definitions.length === 0) {
                     return false;
                 }
 
                 textSource.setEndOffset(length);
 
-            const sentence = docSentenceExtract(textSource, this.options.anki.sentenceExt);
+                sentence = docSentenceExtract(textSource, this.options.anki.sentenceExt);
+            } finally {
+                textSource.cleanup();
+            }
 
             const context = {
                 source: {