Scrollbar on one terminal after spliting vertically (with "show scrollbar" unchecked)

[aichingm]

Describe the bug
Guake shows a scrollbar for one terminal after splitting the terminal vertically, even if "show scrollbar" is unchecked. The scrollbar disappears after toggling the checkbox in the settings window twice.

Expected behavior

The scrollbar should not show up.

Actual behavior

The left terminal is displayed with a scrollbar.

To Reproduce

1. open Guake
2. split the terminal vertically (keyboard shortcut or mouse)

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Guake Version:		3.7.0

Vte Version:		0.60.0

Vte Runtime Version:	0.60.0

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GTK+ Version:		3.24.14

GDK Backend:		GdkX11.X11Display

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Desktop Session: /usr/share/xsessions/plasma

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Display: :0

RGBA visual: True

Composited: True

* Monitor: 0 - HWP HDMI1
    * Geometry:		1680 x 1050 at 1920, 15
    * Size:		470 x 300 mm²
    * Primary:		True
    * Refresh rate:	59.95 Hz
    * Subpixel layout:	unknown
* Monitor: 1 - CMN eDP1
    * Geometry:		1920 x 1080 at 0, 0
    * Size:		280 x 160 mm²
    * Primary:		False
    * Refresh rate:	59.93 Hz
    * Subpixel layout:	unknown