browser (chat): side/panel and keyword handling: - `dialog.Modal` can now be used with a `position` argument. The default `center` keeps the old behaviour of modal in the middle of the screen, while using one of the direction makes the modal appear from top/bottom/right/left with an animation. The closing cross has been removed in favor of clicking/touching any part outside of the modal. - A method to create mockup clones of elements is now used to make placeholders. It is used for the input panel in the main area when it is moved to a sub-panel modal, this way there is not element disappearing. - Clicking on a keyword now shows a sub-messages panel with all messages with this keyword, in a similar way as for threads. Writing a messages there will add the keyword automatically. - Sub-messages panel will auto-scroll when messages are added. rel 458