Dash to panel shape is not changing

My dash to panel is like this:

2 extreme ends are curved, i want it to be retangular actually, how can I do it?

I used dash to panel, and its custom config is like this:

animate-app-switch=true
animate-window-launch=true
appicon-margin=4
appicon-padding=4
available-monitors=[0]
click-action='LAUNCH'
desktop-line-use-custom-color=true
dot-color-1='#5294e2'
dot-color-2='#5294e2'
dot-color-3='#5294e2'
dot-color-4='#5294e2'
dot-color-dominant=false
dot-color-override=false
dot-color-unfocused-1='#5294e2'
dot-color-unfocused-2='#5294e2'
dot-color-unfocused-3='#5294e2'
dot-color-unfocused-4='#5294e2'
dot-color-unfocused-different=false
dot-position='RIGHT'
dot-size=3
focus-highlight=false
focus-highlight-color='#eeeeee'
focus-highlight-dominant=false
focus-highlight-opacity=25
hotkeys-overlay-combo='TEMPORARILY'
intellihide=false
intellihide-hide-from-windows=false
leftbox-padding=-1
middle-click-action='LAUNCH'
panel-element-positions='{"0":[{"element":"showAppsButton","visible":false,"position":"stackedTL"},{"element":"activitiesButton","visible":false,"position":"stackedTL"},{"element":"leftBox","visible":true,"position":"stackedTL"},{"element":"taskbar","visible":false,"position":"stackedTL"},{"element":"centerBox","visible":true,"position":"stackedBR"},{"element":"rightBox","visible":true,"position":"stackedBR"},{"element":"dateMenu","visible":true,"position":"stackedBR"},{"element":"systemMenu","visible":true,"position":"stackedBR"},{"element":"desktopButton","visible":false,"position":"stackedBR"}]}'
panel-element-positions-monitors-sync=true
panel-positions='{"0":"TOP"}'
panel-size=32
shift-click-action='MINIMIZE'
shift-middle-click-action='LAUNCH'
show-appmenu=false
show-favorites=false
show-favorites-all-monitors=false
show-running-apps=false
show-showdesktop-hover=true
show-tooltip=false
show-window-previews=false
status-icon-padding=-1
stockgs-force-hotcorner=false
stockgs-keep-dash=false
stockgs-keep-top-panel=false
stockgs-panelbtn-click-only=false
taskbar-locked=true
trans-use-custom-bg=false
trans-use-custom-gradient=false
trans-use-custom-opacity=false
trans-use-dynamic-opacity=false
tray-padding=-1
tray-size=0
window-preview-title-font-color='#dddddd'

I strongly suggest to use gnome tweak tool Enable shell and user themes extension.

Download and add a custom theme from kde store.

As you can see, my Gnome desktop environment on Debian 10.9 looks like this-

and the Gnome tweak tool configuration is as shown below -

and again, as you can see in the above screenshot that panel hides automatically. Also, the panel has adaptive transparency and is curved; looks as shown-

I hope that my answer turns out to be an act of quite a help,for you.