[BUG] Object St.BoxLayout (0x55c133893030), has been already deallocated

[maxsxu]

• Ubuntu 18.04.1 LTS
• gnome 3.28.3

I got the below error:

(gnome-shell:24631): Gjs-CRITICAL **: 08:52:59.042: Object St.BoxLayout (0x55c133893030), has been already deallocated - impossible to access to it. This might be caused by
the fact that the object has been destroyed from C code using something such as destroy(), dispose(), or remove() vfuncs
== Stack trace for context 0x55c13148e4c0 ==
#0 0x55c131a5ebf0 i   ~/.local/share/gnome-shell/extensions/[email protected]/buttons.js:191 (0x7f58f6b17ab0 @ 30)
#1 0x7ffc568477e0 b   self-hosted:251 (0x7f592cec4ab0 @ 223)
#2 0x55c131a5eb68 i   ~/.local/share/gnome-shell/extensions/[email protected]/buttons.js:189 (0x7f58f6b17a28 @ 23)
#3 0x7ffc568485b0 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7f592ceb5de0 @ 71)
#4 0x55c131a5eae0 i   ~/.local/share/gnome-shell/extensions/[email protected]/buttons.js:452 (0x7f58f6b19450 @ 221)
#5 0x7ffc56849190 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7f592ceb5de0 @ 71)
#6 0x55c131a5ea58 i   ~/.local/share/gnome-shell/extensions/[email protected]/buttons.js:462 (0x7f58f6b195e8 @ 32)
#7 0x7ffc56849d70 I   resource:///org/gnome/gjs/modules/_legacy.js:82 (0x7f592ceb5de0 @ 71)
#8 0x55c131a5e9e0 i   ~/.local/share/gnome-shell/extensions/[email protected]/extension.js:46 (0x7f58f6b01b38 @ 68)
#9 0x55c131a5e920 i   resource:///org/gnome/shell/ui/extensionSystem.js:82 (0x7f592cc5a120 @ 431)
#10 0x55c131a5e8a0 i   resource:///org/gnome/shell/ui/extensionSystem.js:287 (0x7f592cc5a780 @ 13)
#11 0x55c131a5e7d0 i   self-hosted:251 (0x7f592cec4ab0 @ 223)
#12 0x55c131a5e750 i   resource:///org/gnome/shell/ui/extensionSystem.js:284 (0x7f592cc5a560 @ 113)

[catb0t]

looks like a possible use-after-free in GNOME's JavaScript engine, unless no-title-bar's JavaScript does something extremely sketchy I'm guessing this is an upstream edge case

what were you doing to cause the error? it seems to have been triggered by buttons = null i.e. deallocating a buttons object, possibly when the maximised window was unmaximised?