The xSwatch4 theme is already integrated in XOOPS 2.5.11-Beta1 (development version) and also available for download on monxoops.fr for those using XOOPS 2.5.10 (production version).
Downloadable here: xSwatch4-enabled

xSwatch4 is a very functional and modern theme that brings together a large number of advantages for both the site visitor and the webmasters.
Indeed, here are some of its features:

21 themes in 1

Choose a variation of the theme from 21 variations from https://bootswatch.com/4/.
theme using Bootstrap 4 for optimal user experience on smartphone.

Administrator toolbar

Direct access to all administration features from the FrontOffice.

Many overloads in Bootstrap 4

Many module templates available in Bootstrap 4 for Responsive display of your site and pre-installed in the right place.

Direct access to block management

From the FrontOffice, click directly on the block you wish to edit.

Unread private messages PopUp window

Opening a PopUp window for any new unread private messages.

Customize and override Bootstrap definitions

Add your own CSS definitions and override the Bootstrap one.

Coockies

Coockies consent is built into this theme.

Light variant/dark variant switchover

This thème has a light variant if your operating system is in light mode and will switch to a dark variant if your operating system is in dark mode.

Carousel

A carousel with 3 scrolling images has been implemented.

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