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diff --git a/Userland/Libraries/LibWeb/HTML/HTMLCanvasElement.cpp b/Userland/Libraries/LibWeb/HTML/HTMLCanvasElement.cpp
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+++ b/Userland/Libraries/LibWeb/HTML/HTMLCanvasElement.cpp
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+/*
+ * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <AK/Checked.h>
+#include <LibGfx/Bitmap.h>
+#include <LibWeb/CSS/StyleResolver.h>
+#include <LibWeb/DOM/Document.h>
+#include <LibWeb/HTML/CanvasRenderingContext2D.h>
+#include <LibWeb/HTML/HTMLCanvasElement.h>
+#include <LibWeb/Layout/CanvasBox.h>
+
+namespace Web::HTML {
+
+static constexpr auto max_canvas_area = 16384 * 16384;
+
+HTMLCanvasElement::HTMLCanvasElement(DOM::Document& document, const QualifiedName& qualified_name)
+    : HTMLElement(document, qualified_name)
+{
+}
+
+HTMLCanvasElement::~HTMLCanvasElement()
+{
+}
+
+unsigned HTMLCanvasElement::width() const
+{
+    return attribute(HTML::AttributeNames::width).to_uint().value_or(300);
+}
+
+unsigned HTMLCanvasElement::height() const
+{
+    return attribute(HTML::AttributeNames::height).to_uint().value_or(150);
+}
+
+RefPtr<Layout::Node> HTMLCanvasElement::create_layout_node()
+{
+    auto style = document().style_resolver().resolve_style(*this);
+    if (style->display() == CSS::Display::None)
+        return nullptr;
+    return adopt(*new Layout::CanvasBox(document(), *this, move(style)));
+}
+
+CanvasRenderingContext2D* HTMLCanvasElement::get_context(String type)
+{
+    ASSERT(type == "2d");
+    if (!m_context)
+        m_context = CanvasRenderingContext2D::create(*this);
+    return m_context;
+}
+
+static Gfx::IntSize bitmap_size_for_canvas(const HTMLCanvasElement& canvas)
+{
+    auto width = canvas.width();
+    auto height = canvas.height();
+
+    Checked<size_t> area = width;
+    area *= height;
+
+    if (area.has_overflow()) {
+        dbgln("Refusing to create {}x{} canvas (overflow)", width, height);
+        return {};
+    }
+    if (area.value() > max_canvas_area) {
+        dbgln("Refusing to create {}x{} canvas (exceeds maximum size)", width, height);
+        return {};
+    }
+    return Gfx::IntSize(width, height);
+}
+
+bool HTMLCanvasElement::create_bitmap()
+{
+    auto size = bitmap_size_for_canvas(*this);
+    if (size.is_empty()) {
+        m_bitmap = nullptr;
+        return false;
+    }
+    if (!m_bitmap || m_bitmap->size() != size)
+        m_bitmap = Gfx::Bitmap::create(Gfx::BitmapFormat::RGBA32, size);
+    return m_bitmap;
+}
+
+}