I collect here a few macros i have played with.
I have them as Snippets always at hand.


//Remove empty lines (incl. whitespace) - in Selection
document.selection.Replace("^\\s*\\n","",eeFindNext | eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Remove really empty lines only - in Selection
document.selection.Replace("^\\n","",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);


//Reduce many empty lines to one - in Selection
document.selection.Replace("^\\s*$","",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);
document.selection.Replace("(\\n\\n)\\n+","$1",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);


//Reduce many blanks to one - in Selection
document.selection.Replace(" \\s+"," ",eeFindNext | eeFindReplaceEscSeq | eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);
//document.selection.Replace(" {2,}"," ",eeFindNext | eeReplaceAll | eeFindReplaceRegExp);


//Remove every blanks - in Selection
document.selection.Replace("\\s+","",eeFindNext | eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Remove leading blanks - in Selection
//document.selection.Replace("^\\s+(.+)$","$1",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);
document.selection.Replace("^\\s+","",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);


//Remove trailing blanks - in Selection
document.selection.Replace("^(.+?)\\s+$","$1",eeFindNext | eeReplaceAll | eeReplaceSelOnly | eeFindReplaceRegExp);


//Remove first sign from selected lines
redraw = false;
document.selection.Replace("^.","", eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);
document.HighlightFind = false;


//Remove first non-blank sign from selected lines
document.selection.Replace("^(\\s*).(.+)$","$1$2", eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Remove last sign from selected lines
document.selection.Replace(".$","", eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Insert in front of selected lines
Leader = prompt("What to insert in front?","// ");
document.selection.Replace("^",Leader, eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Insert to the end of selected lines
Trailer = prompt("What to insert to the end?"," //");
document.selection.Replace("$",Trailer, eeReplaceSelOnly | eeReplaceAll | eeFindReplaceRegExp);


//Enclose selected word
mySign = prompt( "Enter sign to enclose selection:", "%" );
selText = document.selection.Text;
document.selection.Text = mySign + selText + mySign;


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