HTML for "New Tab Page Injector with Bookmarks" Chrome extension options. Creates a blank canvas for writing or pasting content.

options.html

<style>

* { box-sizing: border-box }


html {
  font-family: sans-serif !important; /* 1 */
  line-height: 1.15 !important; /* 2 */
  -ms-text-size-adjust: 100% !important; /* 3 */
  -webkit-text-size-adjust: 100% !important; /* 3 */
}
body {
  margin: 0 !important;
}
article,
aside,
footer,
header,
nav,
section {
  display: block !important;
}

h1 {
  font-size: 2em !important;
  margin: 0.67em 0 !important;
}
figcaption,
figure,
main { /* 1 */
  display: block !important;
}
figure {
  margin: 1em 40px !important;
}
hr {
  box-sizing: content-box !important; /* 1 */
  height: 0 !important; /* 1 */
  overflow: visible !important; /* 2 */
}
pre {
  font-family: monospace, monospace !important; /* 1 */
  font-size: 1em !important; /* 2 */
}
a {
  background-color: transparent !important; /* 1 */
  -webkit-text-decoration-skip: objects !important; /* 2 */
}
a:active,
a:hover {
  outline-width: 0 !important;
}
abbr[title] {
  border-bottom: none !important; /* 1 */
  text-decoration: underline !important; /* 2 */
  text-decoration: underline dotted !important; /* 2 */
}
b,
strong {
  font-weight: inherit !important;
}
b,
strong {
  font-weight: bolder !important;
}
code,
kbd,
samp {
  font-family: monospace, monospace !important; /* 1 */
  font-size: 1em !important; /* 2 */
}
dfn {
  font-style: italic !important;
}
mark {
  background-color: #ff0 !important;
  color: #000 !important;
}
small {
  font-size: 80% !important;
}
sub,
sup {
  font-size: 75% !important;
  line-height: 0 !important;
  position: relative !important;
  vertical-align: baseline !important;
}
sub {
  bottom: -0.25em !important;
}
sup {
  top: -0.5em !important;
}
audio,
video {
  display: inline-block !important;
}
audio:not([controls]) {
  display: none !important;
  height: 0 !important;
}
img {
  border-style: none !important;
}
svg:not(:root) {
  overflow: hidden !important;
}
button,
input,
optgroup,
select,
textarea {
  font-family: sans-serif !important; /* 1 */
  font-size: 100 !important%; /* 1 */
  line-height: 1.15 !important; /* 1 */
  margin: 0 !important; /* 2 */
}
button,
input { /* 1 */
  overflow: visible !important;
}
button,
select { /* 1 */
  text-transform: none !important;
}
button,
html [type="button"], /* 1 */
[type="reset"],
[type="submit"] {
  -webkit-appearance: button !important; /* 2 */
}
button::-moz-focus-inner,
[type="button"]::-moz-focus-inner,
[type="reset"]::-moz-focus-inner,
[type="submit"]::-moz-focus-inner {
  border-style: none !important;
  padding: 0 !important;
}
button:-moz-focusring,
[type="button"]:-moz-focusring,
[type="reset"]:-moz-focusring,
[type="submit"]:-moz-focusring {
  outline: 1px dotted ButtonText !important;
}
fieldset {
  border: 1px solid #c0c0c0 !important;
  margin: 0 2px !important;
  padding: 0.35em 0.625em 0.75em !important;
}
legend {
  box-sizing: border-box !important; /* 1 */
  color: inherit !important; /* 2 */
  display: table !important; /* 1 */
  max-width: 100% !important; /* 1 */
  padding: 0 !important; /* 3 */
  white-space: normal !important; /* 1 */
}
progress {
  display: inline-block !important; /* 1 */
  vertical-align: baseline !important; /* 2 */
}
textarea {
  overflow: auto !important;
}
[type="checkbox"],
[type="radio"] {
  box-sizing: border-box !important; /* 1 */
  padding: 0 !important; /* 2 */
}
[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
  height: auto !important;
}
[type="search"] {
  -webkit-appearance: textfield !important; /* 1 */
  outline-offset: -2px !important; /* 2 */
}
[type="search"]::-webkit-search-cancel-button,
[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none !important;
}
::-webkit-file-upload-button {
  -webkit-appearance: button !important; /* 1 */
  font: inherit !important; /* 2 */
}
details, /* 1 */
menu {
  display: block !important;
}
summary {
  display: list-item !important;
}
canvas {
  display: inline-block !important;
}
template {
  display: none !important;
}
[hidden] {
  display: none !important;
}



/**
 * Start Vanilla CSS 1.0.2 
 */
h1, h2, h3, h4, h5, h6, b, strong {
	font-weight: bold !important;
}
em, i, dfn {
	font-style: italic !important;
}
dfn {
	font-weight:bold !important;
}
p, code, pre, kbd {
	margin:0 0 1.5em 0 !important;
}
blockquote {
	margin:0 1.5em 1.5em 1.5em !important;
}
cite {
	font-style: italic !important;
}
li ul, li ol {
	margin:0 1.5em !important;
}
ul, ol {
	margin:0 1.5em 1.5em 1.5em !important;
}
ul {
	list-style-type:disc !important;
}
ol {
	list-style-type:decimal !important;
}
ol ol {
	list-style: upper-alpha !important;
}
ol ol ol {
	list-style: lower-roman !important;
}
ol ol ol ol {
	list-style: lower-alpha !important;
}
dl {
	margin:0 0 1.5em 0 !important;
}
dl dt {
	font-weight:bold !important;
}
dd {
	margin-left:1.5em !important;
}
table {
	margin-bottom:1.4em !important;
	width:100% !important;
}
th {
	font-weight:bold !important;
}
th, td, caption {
	padding:4px 10px 4px 5px !important;
}
tfoot {
	font-style:italic !important;
}
sup, sub {
	line-height:0 !important;
}
abbr, acronym {
	border-bottom: 1px dotted !important;
}
address {
	margin:0 0 1.5em !important;
	font-style:italic !important;
}
del {
	text-decoration: line-through !important;
}
pre {
	margin:1.5em 0 !important;
	white-space:pre !important;
}
/**
* End Vanilla CSS
*/

#editable {

  background-color: inherit !important;
  outline: none !important; 
  font-family: serif !important;
  font-size: 1.45rem !important;
  line-height: 1.6em !important;
  text-align: left !important;
  padding: 3em !important;
  max-width: 900px !important;
  margin: auto !important;
  min-height: calc(100vh - 6vw) !important;
  opacity: .75 !important;

}

#editable * {
  display: inline !important;
}

#editable *,
#editable *:hover {
  background-color: inherit !important;
  outline: none !important;
  border: none !important; 
  margin: 0 !important; 
  font-family: inherit !important;
  font-size: 1.45rem !important;
  line-height: inherit !important;
  text-align: left !important;
  padding: 0 !important;
  width: auto !important;
  height: auto !important;
  max-height: 100% !important;
  max-width: 100% !important;
  min-height: 0 !important;
  min-width: 0 !important;
  margin: auto !important;
  color: inherit !important;
  background-color: transparent !important;
  position: static !important;
  float: none !important;
  text-transform: none !important;
  text-decoration: none !important;
  box-shadow: none !important;
  background-image: none !important;
  letter-spacing: normal !important;
  text-rendering: auto !important;
  text-shadow: none !important;
  cursor: text !important;
}

#editable p,
#editable div,
#editable article,
#editable section,
#editable ul,
#editable li,
#editable h1,
#editable h2,
#editable h3,
#editable h4,
#editable h5,
#editable h6,
#editable h7,
#editable h8,
#editable h9,
#editable form,
#editable fieldset,
#editable ol,
#editable pre,
#editable dl,
#editable address,
#editable bloquote, dl {

  display: block !important;

}

#editable table    { display: table !important }
#editable tr       { display: table-row !important }
#editable thead    { display: table-header-group !important }
#editable tbody    { display: table-row-group !important }
#editable tfoot    { display: table-footer-group !important }
#editable col      { display: table-column !important }
#editable colgroup { display: table-column-group !important }
#editable td, th   { display: table-cell !important }
#editable caption  { display: table-caption !important }

#editable figure,
#editable img,
#editable svg,
#editable *:after,
#editable *:before,
#editable canvas,
#editable iframe,
#editable object,
#editable input,
#editable textarea,
#editable button {
  display: none !important;
}

#editable hr {
  height: 2px !important;
  width: 100% !important;
  display: block !important;
  background-color: #eee !important;
  margin-top: 1.5em !important;
}

#editable p,
#editable p:hover,
#editable div,
#editable div:hover,
#editable ul,
#editable ul:hover {
  margin-bottom: 1em !important;
}

#editable ul,
#editable ul:hover { 
   list-style: disc !important;
   list-style-type: disc !important; 
   list-style-position: inside !important;
   margin-left: .5em !important; 
}
#editable ol,
#editable ol:hover { 
   list-style-type: decimal !important; 
   list-style-position: inside !important; 
   margin-left: .5em !important; 
}
#editable ul ul,
#editable ul ul:hover,
#editable ol ul,
#editable ol ul:hover { 
   list-style-type: circle !important; 
   list-style-position: inside !important; 
   margin-left: .5em !important; 
}
#editable ol ol,
#editable ul ol,
#editable ol o:hoverl,
#editable ul ol:hover { 
   list-style-type: lower-latin !important; 
   list-style-position: inside !important; 
   margin-left: .5em !important; 
}
#editable li,
#editable li:hover {
  margin-left: .5em !important;
}

#editable li {
   display: list-item !important;
}

#editable table {
  width: auto !important;
  table-layout: fixed !important;
}

#editable table,
#editable th,
#editable tr,
#editable td,
#editable table:hover,
#editable th:hover,
#editable tr:hover,
#editable td:hover,
#editable thead,
#editable thead:hover,
#editable tbody:,
#editable tbody:hover,
#editable tfoot:,
#editable tfoot:hover {
  border: 0 !important;
  border-collapse: collapse !important;
  border-width: 1px !important;
  border-color: #666 !important;
  border-style: solid !important;
  margin: 0 !important;
}

#editable table tr,
#editable table tr:hover {
  background: transparent !important;
}

#editable table th,
#editable table th:hover {
  background: #eee !important;
}

#editable code,
#editable code:hover,
#editable code *,
#editable code *:hover,
#editable pre,
#editable pre:hover,
#editable pre *,
#editable pre *:hover {
  font-family: monospace, monospace !important;
  font-size: 1.1rem !important;
  color: #555 !important;
}

#editable blockquote,
#editable blockquote:hover {
  display: block !important;
}

#editable blockquote,
#editable blockquote:hover,
#editable blockquote *,
#editable blockquote *:hover {
   color: #aaa !important;
   font-style: italic !important;
   font-weight: normal !important;
}

#editable *:blank {
  display: none !important;
}

#editable:empty:not(:focus):before {

  content: attr(placeholder) !important;
  opacity: .2 !important;
  cursor: text !important;
  font-size: 1.8rem !important;
  position: relative !important;
  top: 0 !important;
  left: -1em;

}

</style>

<div id="editable" contenteditable="true" autofocus="true" placeholder="⇥"></div>