Make the inactive open program pinned icon background color a bit brighter.

[ghost]

It's very hard to see inactive pinned icons at the taskbar.

This is the active icon. Its better visible than the inactive icon.

Could you make the inactive icon background color a bit more brighter?

[Zren]

In ~/.local/share/plasma/desktoptheme/breeze-alphablack/widgets/tasks.svg

normal-top is composed of 2 rectangles with ColorScheme-Text at opacity=0.16 aka white text at 16%. minimized-top is the same.

You can open the svg in a text editor and change the opacity for both of those (including -topleft and -topright). Then restart Plasma by logging out and in.

[Zren]

The default Breeze uses 0.08 for minimized-*, and uses 0.15 for normal-center and 0.33 for normal-top.

    <g id="normal-center" class="ColorScheme-Text" transform="matrix(.96296296 0 0 1 .185185 41.899998)" fill="currentColor" opacity=".15">
        <path id="path413" class="ColorScheme-Text" d="m5 4.1h27v13h-27z" fill="currentColor"/>
    </g>
    <g id="normal-top" class="ColorScheme-Text" transform="matrix(1 0 0 -1 0 71.999998)" fill="currentColor" opacity=".33">
        <path id="rect4997-3-9" transform="scale(1,-1)" d="m5-28h26v2h-26z"/>
        <path id="path417" transform="scale(1 -1)" d="m5-29h26v1h-26z"/>
    </g>
    <g id="minimized-center" class="ColorScheme-Text" transform="matrix(.96296296 0 0 1 .185185 104.89999)" fill="currentColor" opacity=".08">
        <path id="path986" class="ColorScheme-Text" d="m5 4.1h27v13h-27z" fill="currentColor"/>
    </g>
    <g id="minimized-top" class="ColorScheme-Text" transform="matrix(1 0 0 -1 0 135)" fill="currentColor" opacity=".08">
        <path id="path989" transform="scale(1 -1)" d="m5-28h26v1.999988h-26z"/>
        <path id="path991" transform="scale(1 -1)" d="m5-29h26v1h-26z"/>
    </g>