When using Orion windowed the background image of the Startpage extends into the toolbar area as the space surround the interactive icons becomes transparent. 
Putting Orion into fullscreen increases the opacity of the toolbar. In light mode this make the toolbar basically unreadable. 
The readability is better in dark mode. 
Regardless of settings this changing in opacity always happens. This also happens in Vertical and Compact tab mode, it is not a problem in Standard tab mode. It is also not related to colour tinting tabs as turning off that feature doesn't change the behaviour. 
A similar issue can be observed in Safari around the extension icon area. However, it is not a frequent issue and cannot be reproduced reliably, hence no image of it.
I expect the toolbar transparency to remain consistent in the Startpage. I like the toolbar changing colour when navigating tabs but I prefer the Startpage background image stretching up into the toolbar as shown in the screenshot of Orion when windowed.
At the very least I want to toolbar to remain readable when in fullscreen.
Version 0.99.136-beta (WebKit 622.1.15.19.2), Mac 15.7 (Build 24G222)
Sequoia (15)
