thick white border instead of usual hard-to-notice border

[sidmint]

Reproduce [shown in gif]: 1 open gnome system monitor and select button other than 'processes' [that is 'resource' or 'file systems'] 2 open another window, say a file manager 3 close newly opened window to shift focus to gnome system monitor automatically [as it's the recent most app] 4 processes button has this thick white border instead of usual hard-to-notice border usually in other themes.

Linuxmint 19.3 xfce.

[Elbullazul]

that is intentional and in accordance with Microsoft's styling for focused buttons for Metro apps:

if you want to manually remove that styling, I can provide assistance

[sidmint]

Thank you for your active involvement. I'm so content using this theme, best I found till for me.

Styling for focused buttons: Now I understood and find it okay and useful.

But I see some problems while switching it via tab button in gnome system monitor. Rectangle over 'processes' and 'resources' have only 3 white sides, next three selections are good as shown in gif, selection over the process named xfwm4 is not white at all [that may be intentional/exception for that type of area though, is that so?], and the last two selections of 'end process' and another icon [whose tool tip says 'show process properties'] has only one side as white as shown below.

[Elbullazul]

It's caused by the way GTK draws controls. Basically, a child control can't be drawn outside of its parent's boundaries. But to have the intended effect, I had to offset by 2px, so it "fails" to draw some parts of the outline.

I had another look at what grouped buttons look like without the highlight:

there should actually be spacing between button. I should rework the buttons, probably in a short time.

[Elbullazul]

selection over the process named xfwm4 is not white at all [that may be intentional/exception for that type of area though, is that so?]

it is intentional. Only the buttons and text entries (if I remember correctly) are supposed to have that outline style

[Elbullazul]

c1fa436 corrects this issue

[sidmint]

Wow, thanks a lot, it's even more awesome now.