Allow class attribute for tables in purifier config - closes #4429

config/purifier.php

@@ -24,7 +24,7 @@
     'settings'      => [
         'default' => [
             'HTML.Doctype'             => 'HTML 4.01 Transitional',
-            'HTML.Allowed'             => 'div[style],b,strong,i,em,u,a[href|title|style],ul,ol,li,p[style],br,span[style],img[width|height|alt|src|style],table[style|border|bgcolor|cellspacing|cellpadding|border|width],tr[style|bgcolor],td[style|colspan|rowspan|width|bgcolor|border|valign|align],th[style|colspan|rowspan],thead,tfoot,tbody,blockquote,pre,s,strike,font[style|color],h1[style],h2[style],h3[style],h4[style],h5[style],h6,center',
+            'HTML.Allowed'             => 'div[style],b,strong,i,em,u,a[href|title|style],ul,ol,li,p[style],br,span[style],img[width|height|alt|src|style],table[style|border|bgcolor|cellspacing|cellpadding|border|width|class],tr[style|bgcolor],td[style|colspan|rowspan|width|bgcolor|border|valign|align],th[style|colspan|rowspan],thead,tfoot,tbody,blockquote,pre,s,strike,font[style|color],h1[style],h2[style],h3[style],h4[style],h5[style],h6,center',
             'CSS.AllowedProperties'    => 'display,overflow,border-radius,letter-spacing,white-space,font-size,margin,margin-top,margin-right,margin-bottom,margin-left,background,text-transform,max-width,max-height,width,height,font,padding,padding-top,padding-right,padding-bottom,padding-left,font-family,border-color,font-weight,font-style,text-decoration,color,background-color,text-align,border,border-top,border-left,border-bottom,border-right',
             'AutoFormat.AutoParagraph' => true,
             'AutoFormat.RemoveEmpty'   => true,