Hello all. There is current software defect investigation into this (or very similar) issue. I suggest you contact Qlik Support for further assistance.
You asked for version 12.10, At the bottom you mentioned that "In version server : 12.0 SR15 : the two mode work."
But both versions its working fine, I don't see any difference my end.
What browser are you using? Its possible that this is an old browser version that is no longer supported by QV 12.10.
Web view uses IE and it will use whatever version is installed. AJAX view on the server uses the browser opened by the user. So the browser version is relevant to both.
With the desktop in webmode or with the server is the same result. I use Chrome and not IE to see the qv report.
With the webserver 12.0 SR15 the date calendar work but not with the webserver 12.1
I send you my report
I am also having the same issue, have you found the solution?
In webview mode (version 12.1 SR1 ) the selection doesn't appear, while it is fine in desktop mode.