how different browsers handle these filenames:
  [👌.html]
  [lorem"ipsum.html ]
  [lorem\"ipsum.html ]
  [∭.triple.integral]
  [_a_∭_.txt]  (_a_👌_.txt)
  [_"_%_%2_%22_%2f_%25_.txt]  (_"_%_%2_"_%_.txt)
  [_\"_%_%2_%22_%2f_%25_.txt]  (_\"_%_%2_"_%_.txt)
  [abc !"#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt]
  [aabbcc  !!""##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt]

lines starting with "saved file:" is how php7.2.18 decodes it

curl:
  escapes " into \"
  escapes \" into \\\"
  actually doesn't suck

chrome/safari:
  escapes " into %22
  does not escape \
  does not escape %xx so %22 is unmodified (decodes as ")
  does not escape &#xx; so &#97; is unmodified (decodes as a)

firefox:
  escapes " into \"
  however \" becomes \\" so php and most other parsers fail
  also does not escape &#xx; or %xx just like chrome/safari

ie7:
  wins by default since windows filenames can't contain "

conclusion:
  always set <meta charset="utf-8" />
  pretend the mythical filename* does not exist (it doesn't)

  if /AppleWebKit/:
    simple replace from %22 to "
  else:
    if filename contains \\\" or (\\ and not \\"):
	  proper unescape \\ and \"
	else:
	  simple replace \" to "



firefox 66.0.5 linux, no encoding on the html with the <form>
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:66.0) Gecko/20100101 Firefox/66.0
Content-Type: multipart/form-data; boundary=---------------------------2128611736173971212222926164
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\\"ipsum.html "
saved file: _"_%_%2_%22_%2f_%25_.txt
saved file: _&#97;_&#8749;_.txt
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: lorem"ipsum.html
bad filename or other error
saved file: ∭.triple.integral
saved file: 👌.html

chrome 72.0.3626.121 linux, no encoding on the html with the <form>
User-Agent: Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/72.0.3626.121 Safari/537.36
Content-Type: multipart/form-data; boundary=----WebKitFormBoundary5SmRJkwFKdZJDvyi
Content-Disposition: form-data; name="f"; filename="&#128076;.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html "

chrome 72.0.3626.121 linux, <meta charset="utf-8" />
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="_%22_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_\%22_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="abc !%22#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt"
Content-Disposition: form-data; name="f"; filename="aabbcc  !!%22%22##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt"
saved file: _&#97;_&#8749;_.txt
saved file: _%22_%_%2_%22_%2f_%25_.txt
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: ∭.triple.integral
saved file: %22ipsum.html
saved file: lorem%22ipsum.html
saved file: 👌.html

IE7 xp, no encoding on page
User-Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1; .NET CLR 2.0.50727)
Content-Type: multipart/form-data; boundary=---------------------------7e325111400c0
Content-Disposition: form-data; name="f"; filename="C:\Documents and Settings\Administrator\My Documents\Downloads\&#128076;.html"
Content-Disposition: form-data; name="f"; filename="C:\Documents and Settings\Administrator\Desktop\&#8749;.triple.integral"
Content-Disposition: form-data; name="f"; filename="C:\Documents and Settings\Administrator\My Documents\Downloads\_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="C:\Documents and Settings\Administrator\My Documents\Downloads\_&#97;_&#8749;_.txt"

IE7 xp, <meta charset="utf-8" />
Content-Disposition: form-data; name="f"; filename="C:\Documents and Settings\Administrator\My Documents\Downloads\👌.html"

firefox 52.9 xp, no encoding on page
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:52.0) Gecko/20100101 Firefox/52.0
Content-Type: multipart/form-data; boundary=---------------------------283191563824012
Content-Disposition: form-data; name="f"; filename="&#128076;.html"
Content-Disposition: form-data; name="f"; filename="&#8749;.triple.integral"
Content-Disposition: form-data; name="f"; filename="_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"

firefox 52.9 xp, <meta charset="utf-8" />
Content-Disposition: form-data; name="f"; filename="👌.html"

curl 7.64.0 linux
curl -F "f=@\"lorem\\\"ipsum.html \"" http://127.0.0.1:2345/
curl -F 'f=@_"_%_%2_%22_%2f_%25_.txt' http://127.0.0.1:2345/
curl -F 'f=@_\"_%_%2_%22_%2f_%25_.txt' http://127.0.0.1:2345/
User-Agent: curl/7.64.0
Content-Type: multipart/form-data; boundary=------------------------052f235dc0b9bae6
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="_\"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_\\\"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="lorem\"ipsum.html "
# curl cli can't do single " when there's a whitespace too so that was [lorem"ipsum.html ]

firefox 67 osx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:67.0) Gecko/20100101 Firefox/67.0
Content-Type: multipart/form-data; boundary=---------------------------80573919926839611121776207
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="_\"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="abc !\"#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt"
Content-Disposition: form-data; name="f"; filename="aabbcc  !!\"\"##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt"
saved file: _&#97;_&#8749;_.txt
saved file: _%22_%_%2_%22_%2f_%25_.txt
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: ∭.triple.integral
saved file: %22ipsum.html 
saved file: lorem%22ipsum.html 
saved file: 👌.html
# lorem\"ipsum.html becomes %22ipsum.html (the trailing space survives tho)

safari 2019-06-02 osx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.1 Safari/605.1.15
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryBKvsttxCpqAA9G1Q
Content-Disposition: form-data; name="f"; filename="?.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="?.triple.integral"

safari 2019-06-02 osx (with charset=utf-8 in html or headers)
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.1 Safari/605.1.15
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryPBtwBgBwTF1SPLmC
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="_%22_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="abc !%22#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt"
Content-Disposition: form-data; name="f"; filename="aabbcc  !!%22%22##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt"
saved file: _&#97;_&#8749;_.txt
saved file: _%22_%_%2_%22_%2f_%25_.txt
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: ∭.triple.integral
saved file: %22ipsum.html 
saved file: lorem%22ipsum.html 
saved file: 👌.html

chrome 74.0.3729.169 osx
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryj4Pp93BSWa9JBcsE
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html "
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="_%22_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="abc !%22#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt"
Content-Disposition: form-data; name="f"; filename="aabbcc  !!%22%22##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt"
saved file: _&#97;_&#8749;_.txt
saved file: _%22_%_%2_%22_%2f_%25_.txt
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: ∭.triple.integral
saved file: %22ipsum.html 
saved file: lorem%22ipsum.html 
saved file: 👌.html

firefox ios
User-Agent: Mozilla/5.0 (iPod touch; CPU iPhone OS 12_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) FxiOS/17.3b15323 Mobile/15E148 Safari/605.1.15
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryc5YQtKBEkwJ4br42
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html .txt"
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html .txt"
saved file: _%22_%_%2_%22_%2f_%25_.txt 
saved file: _a_∭_.txt 
saved file: lorem%22ipsum.html .txt 
saved file: %22ipsum.html .txt 
saved file: 👌.html 
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt 

safari ios
User-Agent: Mozilla/5.0 (iPod touch; CPU iPhone OS 12_3 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/12.1.1 Mobile/15E148 Safari/604.1
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryrGBKxBdYeZT3kkOd
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="lorem%22ipsum.html .txt"
Content-Disposition: form-data; name="f"; filename="lorem\%22ipsum.html .txt"
saved file: _%22_%_%2_%22_%2f_%25_.txt 
saved file: _a_∭_.txt 
saved file: 👌.html 
saved file: lorem%22ipsum.html .txt 
saved file: %22ipsum.html .txt 
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt 

chrome android:
saved file: _%22_%_%2_%22_%2f_%25_.txt
saved file: ∭.triple.integral
saved file: lorem%22ipsum.html 
saved file: ]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: %22ipsum.html 
saved file: _&#97;_&#8749;_.txt
saved file: 👌.html

firefox android:
saved file: _"_%_%2_%22_%2f_%25_.txt
saved file: _&#97;_&#8749;_.txt
saved file: ∭.triple.integral
saved file: 👌.html
saved file: ]]^^__``{{||}}~~ ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt
saved file: ]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt
saved file: lorem"ipsum.html
bad filename or other error

w3m 0.5.3
User-Agent: w3m/0.5.3+git20180125
Content-Type: multipart/form-data; boundary=------------------------------75771398083265246401398083264094080
Content-Disposition: form-data; name="f"; filename="_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="_"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_\"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="abc !"#$%&'()*+,-.x0123456789:;<=>?@ABC[\]^_`{|}~ ´µ¶·¸¹º»¿⌐¬½¼¡«»░▒▓│─█.txt"
Content-Disposition: form-data; name="f"; filename="aabbcc  !!""##$$%%&&''(())**++,,--..xx00112233445566778899::;;<<==>>??@@AABBCC[[\\]]^^__``{{||}}~~  ´´µµ¶¶··¸¸¹¹ºº»»¿¿⌐⌐¬¬½½¼¼¡¡««»»░░▒▒▓▓││──██..ttxxtt"
Content-Disposition: form-data; name="f"; filename="lorem"ipsum.html "
Content-Disposition: form-data; name="f"; filename="lorem\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="👌.html"

elinks 0.13
User-Agent: ELinks/0.13.GIT (textmode; Linux 4.19.41-0-vanilla x86_64; 146x33-2)
Content-Type: multipart/form-data; boundary=4n5BrUX5050f4cK0I8cOyyMehwiaop8D
Content-Disposition: form-data; name="f"; filename="lorem"ipsum.html "
Content-Disposition: form-data; name="f"; filename="👌.html"

links 2.15
User-Agent: Links (2.15; Linux 4.19.41-0-vanilla x86_64; GNU C 8.2; text)
Content-Type: multipart/form-data; boundary=---------------------------00000000000000000000000000000
Content-Disposition: form-data; name="f"; filename="lorem"ipsum.html "
# can't unicode

lynx 2.8.8_p2
User-Agent: Lynx/2.8.8rel.2 libwww-FM/2.14 SSL-MM/1.4.1 OpenSSL/1.1.1b
Content-type: multipart/form-data; boundary=LYNX
Content-Disposition: form-data; name="f"; filename="./payloads/lorem\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="./payloads/lorem\\\"ipsum.html "
Content-Disposition: form-data; name="f"; filename="./payloads/_&#97;_&#8749;_.txt"
Content-Disposition: form-data; name="f"; filename="./payloads/_\"_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="./payloads/abc !\"#$%&'()*+,-.x0123456789:;<=>?@ABC[\\]^_`{|}~ ´µ¶·¸¹º»¿�\�\�¬½¼¡«»�\�\��\�\��\�\��\�\��\�\��\�\�.txt"
Content-Disposition: form-data; name="f"; filename="./payloads/�\�\�\�.html"  (that was 👌.html)

opera 36 xp
User-Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/49.0.2623.112 Safari/537.36 OPR/36.0.2130.80
Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryKVXR8CgZ2IzmOqGW
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"

opera 11.01 xp
User-Agent: Opera/9.80 (Windows NT 5.1; U; en) Presto/2.7.62 Version/11.01
Content-Type: multipart/form-data; boundary=----------bVWAx7M95jeF3S6MX21SdK
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"

netscape 3.0 xp
User-Agent: Mozilla/3.0 (WinNT; I)
Content-type: multipart/form-data; boundary=---------------------------337238125597
Content-Disposition: form-data; name="f"; filename="C:\DOCUME~1\ADMINI~1\Desktop\up.html"
Content-Disposition: form-data; name="f"; filename="C:\DOCUME~1\ADMINI~1\Desktop\?.triple.integral"

opera 11.01 centos7
User-Agent: Opera/9.80 (X11; Linux x86_64; U; en) Presto/2.7.62 Version/11.01
Content-Type: multipart/form-data; boundary=----------ybnHVeRVJHI1gosrCyUezH
Content-Disposition: form-data; name="f"; filename="%F0%9F%91%8C.html"
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="_%_%2_%22_%2f_%25_.txt"  (the pre-escaped _\" was truncated)
Content-Disposition: form-data; name="f"; filename="_&#97.txt"
# both lorem"ipsum.html and lorem\"ipsum.html fail, probably due to the trailing whitespace
# breaks on files with quotes in the name unless they are pre-escaped with \ lol
# NOTE: enters multipart/mixed with multiple files (nested multipart with different boundaries)
# multiple form fields are fine however
# keeps form field order

opera 11.10 centos7
User-Agent: Opera/9.80 (X11; Linux x86_64; U; en) Presto/2.8.131 Version/11.10
# now it does multiple files correctly but fails to upload the contents of files with emojis in the name?? just leaves the body blank laff
# keeps form field order

opera 12.00 centos7
User-Agent: Opera/9.80 (X11; Linux x86_64; U; en) Presto/2.10.289 Version/12.00
Content-Type: multipart/form-data; boundary=----------Kjv0zd9NpPWFRkicPTZf8C
Content-Disposition: form-data; name="f"; filename="👌.html"
Content-Disposition: form-data; name="f"; filename="∭.triple.integral"
Content-Disposition: form-data; name="f"; filename="_%_%2_%22_%2f_%25_.txt"
Content-Disposition: form-data; name="f"; filename="_&#97.txt"
# now it can upload file contents but it still breaks on some ascii special-chars
# keeps form field order

firefox 1 xp
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.5) Gecko/20041107 Firefox/1.0
Content-Type: multipart/form-data; boundary=---------------------------41184676334
Content-Disposition: form-data; name="f"; filename="__.html"
# keeps form field order

firefox 2 xp
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.4) Gecko/20070515 Firefox/2.0.0.4
Content-Type: multipart/form-data; boundary=---------------------------261993242624524
Content-Disposition: form-data; name="f"; filename="👌.html"
# firefox 4.0.1 introduces multiple files and it works



# start upload server, use either of these depending
ncat -l -p 2345
nc -l 2345

# minimal html document for correct behavior in safari
<!DOCTYPE html><html><head><meta charset="utf-8" /></head><body>
<form method="post" action="http://127.0.0.1:2345/" enctype="multipart/form-data">
<h5><input type="file" name="f" multiple="multiple">
<h5><input type="submit" value="start upload">