Add native background image / watermark support for Books and Pages (transparent logo as subtle background)

Dear team,

Currently, Planning Analytics Workspace (PAW) Books only allow a solid background color (via Book Properties → Background color). There is no built-in option to set a background image (e.g., a semi-transparent PNG logo) that acts as a true watermark or subtle corporate branding element across an entire page or book.

Workaround in use today:
Users insert a PNG image (with transparency) as an Image widget, stretch it to cover the full page, reduce its opacity (via pre-editing or image properties), and send it to the back (Order → Send to Back). This creates a watermark-like effect, but it has several limitations:

• The image remains a floating widget, not a native background layer

• It can interfere with widget alignment, snapping, responsive layouts, or z-order when overlapping with selectors/views

• Scaling/positioning often requires manual tweaks on different screen sizes or when exporting to PDF

• No native options for cover/contain, fixed positioning, tiling, or automatic opacity control

Desired enhancement:
Add native support for background images at the Book and/or Page level, similar to features in Power BI, Tableau, or web-based reporting tools. Ideal features would include:

• Upload/reference a .png / .svg file in Book/Page Properties

• Opacity slider (e.g., 5–40%) for watermark effect

• Positioning options: Cover, Contain, Center, Tile, Fixed/Scroll behavior

• Dedicated "Watermark mode" toggle for images (auto-send to back, lock as non-interactive background layer)

• Optional propagation via Custom Themes for default corporate watermark across all books

Business value:

• Enables professional, consistent corporate branding in executive dashboards and reports

• Eliminates time-consuming manual layering hacks

• Improves visual cleanliness and PDF/print exports

• Aligns PAW more closely with modern BI tools for better user adoption

This seems to be a common ask in the community over the years — adding it would be a high-impact, relatively straightforward improvement.

Thanks for considering!

With best regards,
Vitalij