Validation errors W3C, Grayscale

<p><span>Hello <br />=0D=0A</span></p>=0D=0A<p><span>I have check=
ed my site with W3C validators (<a href=3D"http://jigsaw.w3.org/c=
ss-validator/">http://jigsaw.w3.org/css-validator/</a>) and they =
found the following errors:</span></p>=0D=0A<p><span>&nbsp;</span=
></p>=0D=0A<p><span>.</span></p>=0D=0A<p><strong><span>URI:</span=
></strong></p>=0D=0A<p><strong><span>/wp-content/plugins/wp-acces=
sibility/toolbar/css/a11y.css?ver=3D4.0.1</span></strong></p>=0D=0A=
<p><strong><span>&nbsp;</span></strong></p>=0D=0A<p><strong><span=
>Lines:</span></strong></p>=0D=0A<p><strong><span>109 .desaturate=
d Property filter doesn't exist: grayscale(100%)</span></strong><=
/p>=0D=0A<p><strong><span>115 .desaturated Property filter doesn'=
t exist: url("data:image/svg+xml;utf8,&lt;svg xmlns=3D\'http://ww=
w.w3.org/2000/svg\'&gt;&lt;filter id=3D\'grayscale\'&gt;&lt;feCol=
orMatrix type=3D\'matrix\' values=3D\'0.3333 0.3333 0.3333 0 0 0.=
3333 0.3333 0.3333 0 0 0.3333 0.3333 0.3333 0 0 0 0 0 1 0\'/&gt;&=
lt;/filter&gt;&lt;/svg&gt;#grayscale")</span></strong></p>=0D=0A<=
p><strong><span>116 .desaturated Property filter doesn't exist: g=
ray </span></strong></p>=0D=0A<p><span>&nbsp;</span></p>=0D=0A<p>=
<span>.</span></p>=0D=0A<p><span>1. I am using&nbsp; WordPress &a=
mp; WP Accessibility plugin. </span></p>=0D=0A<p><span>2. I need =
to have the grayscale converter to my site for Disabled Persons.<=
/span></p>=0D=0A<p><span>3. My site has to pass W3C validation.</=
span></p>=0D=0A<p><span>&nbsp;</span></p>=0D=0A<p><span>I would a=
ppreciate any help. </span>Thanks again.</p>=0D=0A<p>&nbsp;</p>=0D=0A=
<p>Ever grateful</p>