Remove Advertisement from Gmail in FireFox

Opera / Firefox User:
1. Install add-on stylish.
2. Select "write new style" option, and add the following code to build a css file.

RemoveGmailAd.css

.ii.gt,.ii.gt *{font-size:14px !important;line-height:1.5 !important}
/*Hide Advertisement*/
table.T1HY1.nH.iY{width:100% !important;}
table.Bs.nH.iY td.Bu:last-child{display:none;}
/*Hide Quick Action*/
table.T1HY1.nH.iY td.tELAdc:last-child{/*position:absolute !important;top:-65px !important;left:0 !important;*/display:none}
table.T1HY1.nH.iY td.tELAdc:last-child .nH{width:auto !important}
table.T1HY1.nH.iY td.tELAdc:last-child .hk{float:left !important;margin-left:1em !important;}
/*Hide Sending Invitation to Friends*/
.nH.pp.ps .pY{display: none !important;}

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