After entering to, subject and message, the send button should become active so I can send new messages

The button remains inactive, see screenshot above. Replying to an existing message works fine, though.
Mail app version: 1.1.3
Mailserver or service: Postfix
Operating system: Ubuntu-18.04
Web server: Apache
Database: MariaDB
PHP version: 7.2
Nextcloud Version: 18.0.1 and 18.0.2 - I created a common mail configuration for all users via Groupware - MailApp
Browser: Chrome 80.0.3987.132
Operating system: Ubuntu
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I tried to activate the button via browser developer tools. Pressing "send" afterwards leads to this:

Strange: Sending mails works when replying to an existing message...
You didn't select the recipient. Click the suggested row in the dropdown to make a selection.
Sorry for the confusion. We have to improve this.
@ChristophWurst : I'm trying to select the recipient, but it does not seem to be possible. Clarification: It is possible, but strange...
Afterwards, the "send" button is active and sending the email works OK.
Yep, that is the UX flaw I tried to describe.
I don't think there is a better description of the problem, so let's actually keep this ticket open.
Related discussion:
https://help.nextcloud.com/t/mail-send-buttion-greyed-out/77114
Looks like the UX should be improved here.
The "To" and "Cc/Bcc" fields have some additional UX issues when compared to other mail apps:
@nextcloud/mail who can help with this?
I have a behavior I did not see described here yet, but is related:
Trying to type a new email address into the To: field starts showing the pop-up selector that takes over what is written into the To: field for the first letters, but then stops.
I can continue to write the full email into the To: field behind the selector, but the selector stays with these first letters.
(How many is quite arbitrary, seems to depend on the writing velocity in the beginning: What was already written at the startup processing of the pop-up selector is taken, the rest not any more.)
The app will not accept the written address in the To: field, but only the stuff from the pop-up selector. Having the address in the To: field and selecting one of the multiple available empty lines from the selector provides me with an activation of the send button, but when I click the send button, it either gives an error message about a missing sender or once it even said Sent! but nothing is received at the address from the To: field.
Very wired! Makes the sending of new emails (where you cannot reply) impossible. :-(((
I have this behavior in current Chromium and Firefox on Ubuntu 18.4. with Mail 1.1.2 and NC 18.0.3.
Looks like it is a problem/flaw of the multiselect given by nextcloud. I just tried using the original multiselect, like as follows (adding vue-multiselect to package.json first):
// import Multiselect from '@nextcloud/vue/dist/Components/Multiselect'
import Multiselect from 'vue-multiselect'
Here it behaves better/as in the examples found in the docs. Maybe someone needs to take a look what is happening with multiselect in nextcloud-vue.
:eyes: @skjnldsv
Hi there....is this "bug" still open? It is such a basic function to send mails and we plan to show that great product more to the people but with bugs like this...its hard to say. Is there a workarround? we use nextcloud for docker Version 19.0.0 / Mail 1.3.5. now 1.4.0
Kind regards and I hope you can fix that...
@Minocula as you can tell from the activity there were no updates.
As mentioned here https://github.com/nextcloud/mail/issues/3242 pressing tab after typing a name should add that recepient.
That issue is now closed because this functionality should be covered by this issue here.
Issues we found during the brainstorming:
@jancborchardt
We modify the component so that when you click into the field, it doesn’t show in the input anymore – this is confusing and we should just use the default.
Do you mean the manual written search-text should be deleted? If not, this should be added as well ti this issue. It's annoying to have to delete the written search-text to add the next recipient.
No, nothing should ever be deleted from the input unless people specifically delete it via backspace or pressing on the x next to the email chips. :)
What I mea is that it's weird that if you e.g. have 2 emails in the "To" field and click in it, the 2 emails vanish and only show in the dropdown. The component we use (https://vue-multiselect.js.org ) does not do this, and it's much better.
Maybe you didn't really understand what I meant: If I want to enter multiple recipients, I start typing "jan b" for example. Then Jan Borchardt appears in the drop-down list and I select him. I would like to select Christoph Wurst as another recipient. So I start typing, but there is still "jan b" in the editbox - although I have already added Jan Borchard. So I have to delete "jan b" from the edit box before I can start typing "christoph...".
Are you sure that this is the desired behaviour I get upset about it every time.
If it's meant to be, it would be a compromise to highlight the letters you typed. Then I can either delete them with one keystroke or keep the already entered text by typing "arrow left" once.
@ChristophWurst can you put this on the road map? https://github.com/nextcloud/mail/projects/10
IMO this is the biggest UX bug at the moment.
We are aware of that, thanks. Roadmap is merely for features.
Most helpful comment
Issues we found during the brainstorming: