I am wondering can I please get help with this question: tex.stackexchange.com/questions/615819/…

@barbarabeeton I know it's not your problem any more but tex.stackexchange.com/a/615831/1090

I found a bug (or a feature):

@MakeMeSmarterEveryDay it doesn't let me use the edit to see what you used. having to double protect characters that are special to markdown and tex is quite common though, if that is the issue?

> This is an example that shows how quote markdown can interfere MathJax. $ E
> =mc^2$.

The second "greater than" symbol is the culprit.

@MakeMeSmarterEveryDay I'd say you were optimistic hoping that would work, you can't expect to interleave markdown within the fragment that's going to be passed to mathjax (although it works sometimes)

OK. So there will be an easy method to solve it?

Rather than removing the second greater than symbol, I meant.

@MakeMeSmarterEveryDay > This is an example that shows how quote markdown can interfere MathJax. $ E =mc^2$.

@MakeMeSmarterEveryDay what's the advantage in splitting the source over two lines. But I have no information about how stackexchange filters the markdown, they may have some other quoting mechanism in place.

Sometimes users copy and paste a lengthy passage with a lot of MathJax. So there will be a case where the MathJax gets split into 2 or more lines.

@MakeMeSmarterEveryDay yes perhaps. We don't have mathjax running here, so I haven't much experience with mathjax in stackexchange markdown. So someone may answer but my guess is that it gets classed as a feature

@DavidCarlisle quack

@PauloCereda b

@DavidCarlisle oh no

By the way, thank you very much. I think the problem is not too dangerous so let us end the discussion. :-)

@DavidCarlisle finger slipped?

@MakeMeSmarterEveryDay I had a thought:-) posted an answer

@UlrikeFischer no just conservation of energy, only used the minimum required for @PauloCereda to get the full message

@DavidCarlisle Very good. Thanks!

@DavidCarlisle dpc.zip :)

@UlrikeFischer ooh maybe it's a biscuit then

@PauloCereda no

@DavidCarlisle oh no

@DavidCarlisle ^^^ ams?

@UlrikeFischer I was going to blame @PauloCereda

@DavidCarlisle oh no

@UlrikeFischer I wonder if other class caption handling is doing something similar

@DavidCarlisle I didn't look at the details. Do they do something very special?

@UlrikeFischer they have added weird offsets for the usual paragraph case so the caption box ends up with kerns of -1in at start and end of the text (followed by parfillskip at the end) so to make the oneline hbox version for small captions it does \unhbox\@ne\unskip\unskip\unpenalty\unkern to try to clean up but in 2021 that final \unkern just removes the new 0pt guard kern leaving a negative inch kern which pushes centering off by half an inch.

@UlrikeFischer but I'm not totally sure where the kern0pt comes from

@DavidCarlisle Frank just pointed to page 13 in ltpara-code.pdf

@UlrikeFischer yes but if I just set a paragraph in a vbox and \showbox I don't see kern0pt appearing in general with the 2021 release

@UlrikeFischer ah I found it

@MarcelKrüger nice new package you got there :)

@Skillmon Germans <3

The moderator of the Dante meeting has problems to identify the next speaker:

@UlrikeFischer oopsie

I think it's the Musterthomas guy

:)

@DavidCarlisle -- I infer from your last comment on your answer that this is your "ams ping"? When you confirm, I'll send it on. (Have you tested to see what another unkern will result in with TeX Live 2019? I think that's the current production version. If that doesn't work, ...)

@barbarabeeton no I'll send a message to the support address if need be but actually I think we are going to change latex instead (running some tests now) the unkern will be Ok in practice in older releases. It's probably actually more of an issue for @yo' and @PauloCereda as not sure can get a fix out before texlive 2021 ships on overleaf

@Skillmon you just beat me to that lua keys thing but I was held up as I couldn't get it to parse my test option strings

\usepackage[aaa,bbb=1 2 3 4,ccc={1 2 3 4},zz=red]{MWE}

@DavidCarlisle -- Thanks. I'll just continue my periodic grumbles to my remaining contact from time to time, but will ignore this one,

@DavidCarlisle oh, that's understandable. I guess the syntax of what is considered one key and what isn't is a bit strange... :)

@DavidCarlisle I guess the problem is that luakeys tries to guess the data types of the options, and when it hits 1 2 3 4 it treats the 1 as a number, and the rest as separate keys. But I have no idea why it does treat 2, 3, and 4 as separate entries with a space as separator. To get the output you'd expect from a LaTeX point of view you'd have to use quotes: \RequirePackage[aaa,bbb="1 2 3 4",ccc={1 2 3 4},zz=red]{MWE}.

@Skillmon annoying about the edef as well, I wonder if I should have been braver when adding the raw options

@DavidCarlisle I think so. With this new method you get the worst of two worlds, really. If you want to use the raw options you still have to protect things against expansion, but this way you might not get what you want inside the raw options. But I'm not sure what would've been the best way to not use the \edef. If you get rid of that you definitely break backwards compatibility with old documents.

@Skillmon I was wondering if it would be possible to delay the edef to \processOptions which would probably be ok for standard processing but who knows what patched extensions do

@DavidCarlisle That would certainly work for packages/classes using LaTeX's builtin options, but things like pgfopts or l3keys2e, etc., would perhaps break if they assume sanitized input. This could (in theory) break usages in which a user used a space inside a key name where they shouldn't have been one from the package point of view.

@DavidCarlisle with the new macro patching code in the kernel one could delay the \edef step until the various process-option macros of the packages (hello firstaid...). But that would require quite a few packages being covered by firstaid (not expkv-opt though :)

@Skillmon yes but by the time you've got that far tempting to only pass on the raw list and update the packages to apply zap@space themselves if they need that, but at the time that seemed too big a change

@Skillmon I want to do the edef on the old list in a try-catch .....

@Skillmon could the format do this

\RequirePackage{color}

\makeatletter
\protected@edef\zz{\zap@space a=b, c=\sqrt{x+y},z=\color{red}, bb=1 2 3 4 \@empty}
\show\zz

already \protected things don't expand, this would do same for \protect and mean most reasonable things would be error free (if teh raw list is being used it doesn't really matter what this results in so long as it doesn't error, but mostly it results in something sensible, I think)

@DavidCarlisle the "\def\document" guy seems still to have problems chat.stackexchange.com/transcript/message/59175728#59175728

@UlrikeFischer I left a comment, the class is really magical, it's a latex2.09 style with a minimal mostly broken update for 2e so it's never worked but apparently the university has been using for letters all that time

@DavidCarlisle they should have used latex2.09ε

@StefanKottwitz or don't write letters

@DavidCarlisle yep, sorry Grandma

@StefanKottwitz hope your Grandma is doing OK, does she know she is famous?

@DavidCarlisle I told her before she left us, and for me this is my memorial now

@StefanKottwitz ah sorry. I misunderstood your comment above.

@DavidCarlisle that was just generic about letters, no worries

Writing letters is more a thing with earlier generations

@StefanKottwitz certainly true

@DavidCarlisle I guess I wrote 2 letters in 12 years, on paper

@DavidCarlisle it's hard if you don't find your LaTeX letter template from 8 years ago that should be on some of the backup thingies

@DavidCarlisle Apart from letters, I had to do a CV in Word because my old .tex one is on an encrypted NAS that I used on my now broken PC, both in the basement ...

@StefanKottwitz ooh do you still have the kitchen server?

@PauloCereda it got downgraded, it's now a basement server

@StefanKottwitz ooh

@PauloCereda I have to admit, the line "baby, want to see my kitchen server?" worked better than pointing down to the basement

@StefanKottwitz is Faruk around too?

@PauloCereda my friend Farouk had to leave us, after 14 years, but he is still around I feel

@StefanKottwitz oh I am so sorry to hear /hug

@PauloCereda we hard hard weeks with despair and all kind of tries (several roentgen, computer tomography, therapies) at the end it was a salvation for our friend

@PauloCereda but thanks for asking, it's good to remember a friend

sorry to mention in chat, it's life, and you asked, and it's ok to talk when it doesn't hurt anymore, because, it's life.

@PauloCereda my 3 kids are fine, they just complain that dad is too often in the basement

where can we have datacenters, marijuana farms, and meth labs, except in the basement

attic? everybody sees it when the first snow comes and is everywhere except on your roof

now I expect visitors :-D

@PauloCereda I'll send you some domain cc auth codes before they enter

ooh I can post them here in chat

@PauloCereda tell me something regular life stuff before that confused dude continues

@StefanKottwitz ooh hold on I got this

@PauloCereda typo, it's hodl

@StefanKottwitz the three musketeers were actually four :)

@StefanKottwitz fixed :)

@PauloCereda you don't know hodl?

@StefanKottwitz er... No.. .

@PauloCereda that's why you are not rich

@StefanKottwitz ooh money

@PauloCereda google it (hodl, not money)

Don't tell me it's a crypto thingy

Ooh it is

@PauloCereda you should be an expert on real money

@PauloCereda be strong, my friend: it's a crypto thingy

@DavidCarlisle and lack thereof :)

@StefanKottwitz ooh teh future

@PauloCereda and I said, regular life stuff and not crypto future :-) but musketeers was a good try, pretty close to regular life.

My basement camera was enabled.

Good evening to all users.