Minifying javascript via unicode

on dwitter.net i often see dweets that are encoded interestingly to minify the JS to character count.

for example https://www.dwitter.net/d/22372

eval(unescape(escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`.replace(/u../g,'')))

Now I understand how to decode this and read the javascript, it's pretty trivial

unescape(escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`.replace(/u../g,''))

returns

x.font='2em a',x.fillText('\u2620 ',3,25)
t?0:d=x.getImageData(0,0,v=36,v).data
for(c.width|=w=i=936;i--;)e=i%v*6,d[i*4+3]>50||x.fillRect(X=e+e/2*S(t-i/w)+w,i/3-e*C(t-X/99)+e+50,9,i<1?w:9)

but what I don't understand is how to encode js like this.

I noticed there is an intermediary step in this process

running:

escape`𮀮𩡯𫡴🐧𜡥𫐠𨐧𛁸𛡦𪑬𫁔𩑸𭀨𙱜𭐲𝠲𜀠𙰬𜰬𜠵𚐊𭀿𜀺𩀽𮀮𩱥𭁉𫑡𩱥𡁡𭁡𚀰𛀰𛁶🐳𝠬𭠩𛡤𨑴𨐊𩡯𬠨𨰮𭱩𩁴𪁼👷👩🐹𜰶𞱩𛐭𞰩𩐽𪐥𭠪𝠬𩁛𪐪𝀫𜱝🠵𜁼𯁸𛡦𪑬𫁒𩑣𭀨𦀽𩐫𩐯𜠪𤰨𭀭𪐯𭰩𚱷𛁩𛰳𛑥𚡃𚁴𛑘𛰹𞐩𚱥𚰵𜀬𞐬𪐼𜐿𭰺𞐩`

returns

%uD878%uDC2E%uD866%uDC6F%uD86E%uDC74%uD83D%uDC27%uD832%uDC65%uD86D%uDC20%uD861%uDC27%uD82C%uDC78%uD82E%uDC66%uD869%uDC6C%uD86C%uDC54%uD865%uDC78%uD874%uDC28%uD827%uDC5C%uD875%uDC32%uD836%uDC32%uD830%uDC20%uD827%uDC2C%uD833%uDC2C%uD832%uDC35%uD829%uDC0A%uD874%uDC3F%uD830%uDC3A%uD864%uDC3D%uD878%uDC2E%uD867%uDC65%uD874%uDC49%uD86D%uDC61%uD867%uDC65%uD844%uDC61%uD874%uDC61%uD828%uDC30%uD82C%uDC30%uD82C%uDC76%uD83D%uDC33%uD836%uDC2C%uD876%uDC29%uD82E%uDC64%uD861%uDC74%uD861%uDC0A%uD866%uDC6F%uD872%uDC28%uD863%uDC2E%uD877%uDC69%uD864%uDC74%uD868%uDC7C%uD83D%uDC77%uD83D%uDC69%uD83D%uDC39%uD833%uDC36%uD83B%uDC69%uD82D%uDC2D%uD83B%uDC29%uD865%uDC3D%uD869%uDC25%uD876%uDC2A%uD836%uDC2C%uD864%uDC5B%uD869%uDC2A%uD834%uDC2B%uD833%uDC5D%uD83E%uDC35%uD830%uDC7C%uD87C%uDC78%uD82E%uDC66%uD869%uDC6C%uD86C%uDC52%uD865%uDC63%uD874%uDC28%uD858%uDC3D%uD865%uDC2B%uD865%uDC2F%uD832%uDC2A%uD853%uDC28%uD874%uDC2D%uD869%uDC2F%uD877%uDC29%uD82B%uDC77%uD82C%uDC69%uD82F%uDC33%uD82D%uDC65%uD82A%uDC43%uD828%uDC74%uD82D%uDC58%uD82F%uDC39%uD839%uDC29%uD82B%uDC65%uD82B%uDC35%uD830%uDC2C%uD839%uDC2C%uD869%uDC3C%uD831%uDC3F%uD877%uDC3A%uD839%uDC29

which then gets regex replaced with .replace(/u../g,''), but getting this string from minified javascript isn't easy for me.

simply running encodeURIComponent() or escape() doesn't get you quite there, though it gets you part of the way there.

So how do I get the string of my javascript converted into a string containing %uD then the character code for each?



Read more here: https://stackoverflow.com/questions/66992598/minifying-javascript-via-unicode

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