Shalom.
Dear Google, this is a cry for help.
It seems that the new GMail compose interface overrides Firefox’s Ctrl-Shift-X shortcut, which switches the writing direction. It also overrides the right-click->Switch writing direction function; it simply doesn’t do anything.
I cannot do this in Google Chrome either, because of bug 91178 – There seems to be no way to set an input’s direction on Linux nor Chrome OS.
I can probably switch the direction by using rich text, but using rich text has its own issues, and I usually want to send my email in plain text.
Dear Google, please fix this. I tried the new compose interface several times and I complained about this problem in emails to my googler friends. Unfortunately this is still not fixed, and starting from today I can’t go back to the old compose interface.
I understand, of course, that GMail is a free service that doesn’t come with a warranty. Dear Google, I am asking you a favor. You did, in fact, contribute quite a lot to the development of support for right-to-left languages on the Web. I am only asking you to keep this support good.
Thank you.
P.S. Dear Google, please ask Google employees who speak right-to-left languages to use Google products in these languages, and to write email in these languages. Dog-fooding is the best testing. Thank you, again.
Aharoni in Unicode 
Google claims to switching directions. A support page shows an image that looks like the new interface with a button to switch directions.
https://support.google.com/mail/answer/40283?hl=en
The button didn’t appear for me, so I told Google the page was unhelpful and explained I didn’t see how to enable the button.
Any other suggestions on how to complain to Google?
This might or might now work, but in any case this is only for rich text mode. It is not for plain text mode. I need direction switching for plain text mode. It only changes it for the sender and not for the receiver, but it’s nevertheless essential.
I submitted a Tech Evangelism bug on your behalf. https://bugzilla.mozilla.org/show_bug.cgi?id=910490
Hopefully the member of the evangelism team I cc’ed on the bug has some Google contacts.
Gmail support of plaintext has been sub par for years. In fact, it has been on par — with Outlook. Both systems are opinionated, and their opinion is that mail should be rich text. Sad, but I don’t see how to change that.
In particular, it’s not just BiDi that’s broken — whenever a GMailer answers a mail with quotations, breakage ensues. I can’t imagine that Google doesn’t know about this — they just don’t give a damn about plaintext.
That is why I don’t use GMail, and advocate against its use (the servers are ok, it’s just the web client that’s broken).