PRO: Save WS messages as file doesn't work if the contents are too big

[ceifa]

42K messages with ~100kb in average.

helpers.js:118 Uncaught RangeError: Invalid string length
    at Array.join (<anonymous>)
    at Rv.exportMessages (stream-message-list-card.tsx:160:18)
    at Object.Ce (react-dom.production.min.js:54:317)
    at Fe (react-dom.production.min.js:54:471)
    at react-dom.production.min.js:55:35
    at Pr (react-dom.production.min.js:105:68)
    at Rr (react-dom.production.min.js:106:380)
    at react-dom.production.min.js:117:104
    at lc (react-dom.production.min.js:274:42)
    at xe (react-dom.production.min.js:52:375)
    at Wr (react-dom.production.min.js:109:469)
    at Vt (react-dom.production.min.js:74:59)
    at Qt (react-dom.production.min.js:73:73)
    at HTMLDivElement.i (helpers.js:96:17)

I already have a fix on a branch, but I will test it better before making a PR.

[pimterry]

Ah, so that's 42,000 * 100,000 bytes = roughly 4.2GB of data? Yes, exporting that as a single file is likely to break some things! Combining as arraybuffers instead of strings should avoid the length limit itself, but you may hit later issues. We could also try zipping this export, which isn't particularly challenging to do, but it's hard to know how much benefit that'd provide in practice and it does add some complexity.

This is certainly something where filtering options to better manage what's being exported (#163) like you suggested would be helpful.

Out of interest, what are you planning to do with an export of messages like this? How are you going to process it? I had assumed people mostly exported either entire lists of relatively small numbers of messages, or exported individual interesting messages from long streams, rather than exporting the an entire huge stream itself, since this much data will be mildly tricky to handle in plenty of other tools elsewhere too.