1 files changed, 38 insertions, 2 deletions

diff --git a/ext/fg/js/source.js b/ext/fg/js/source.js
index a360b331..e724488d 100644
--- a/ext/fg/js/source.js
+++ b/ext/fg/js/source.js
@@ -25,13 +25,20 @@ const IGNORE_TEXT_PATTERN = /\u200c/;
  */
 
 class TextSourceRange {
-    constructor(range, content='') {
+    constructor(range, content, imposterContainer) {
         this.range = range;
         this.content = content;
+        this.imposterContainer = imposterContainer;
     }
 
     clone() {
-        return new TextSourceRange(this.range.cloneRange(), this.content);
+        return new TextSourceRange(this.range.cloneRange(), this.content, this.imposterContainer);
+    }
+
+    cleanup() {
+        if (this.imposterContainer !== null && this.imposterContainer.parentNode !== null) {
+            this.imposterContainer.parentNode.removeChild(this.imposterContainer);
+        }
     }
 
     text() {
@@ -61,6 +68,10 @@ class TextSourceRange {
         return this.range.getBoundingClientRect();
     }
 
+    getWritingMode() {
+        return TextSourceRange.getElementWritingMode(TextSourceRange.getParentElement(this.range.startContainer));
+    }
+
     getPaddedRect() {
         const range = this.range.cloneRange();
         const startOffset = range.startOffset;
@@ -204,6 +215,23 @@ class TextSourceRange {
 
         return state.remainder > 0;
     }
+
+    static getParentElement(node) {
+        while (node !== null && node.nodeType !== Node.ELEMENT_NODE) {
+            node = node.parentNode;
+        }
+        return node;
+    }
+
+    static getElementWritingMode(element) {
+        if (element === null) {
+            return 'horizontal-tb';
+        }
+
+        const style = window.getComputedStyle(element);
+        const writingMode = style.writingMode;
+        return typeof writingMode === 'string' ? writingMode : 'horizontal-tb';
+    }
 }
 
 
@@ -221,6 +249,10 @@ class TextSourceElement {
         return new TextSourceElement(this.element, this.content);
     }
 
+    cleanup() {
+        // NOP
+    }
+
     text() {
         return this.content;
     }
@@ -267,6 +299,10 @@ class TextSourceElement {
         return this.element.getBoundingClientRect();
     }
 
+    getWritingMode() {
+        return 'horizontal-tb';
+    }
+
     select() {
         // NOP
     }