Flarum core has a CSS rule saying "On mobile, hide all composer controls except the back control".
As a workaround, right now you can get the button to show with this custom css
@media (max-width: 767px) {
.normal .ComposerBody-header>li:first-child {
margin-left: 75px;
margin-right: 75px;
}
.Composer:not(.minimized) .Composer-controls li.item-save-draft {
display: block;
position: absolute !important;
z-index: 1001;
top: 0 !important;
left: 35px;
>.Button {
height: 46px;
padding: 13px !important;
}
}
}
It's not something I would want to add to the extension. Rather it should be changed in core since it prevents being able to extend the composer controls.
<vodka>
I'm afraid Flarum's CSS is a serious mess that doesn't implement any of the principles of extensibility that Flarum stands for. As impressed as I am with the backend architecture, I'm shocked at the lack thereof in the front-end, the way CSS is applied specifically. The sheer number of dead rules and uses of !important show that.
</vodka>