giu: [bug] examples/widgets broken on cimgui-go

What happend?

Failed to start with following error log.

2023-09-22 21:26:48.585 widgets[70477:6681227] *** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'nextEventMatchingMask should only be called from the Main Thread!'
*** First throw call stack:
(
        0   CoreFoundation                      0x00000001824fb154 __exceptionPreprocess + 176
        1   libobjc.A.dylib                     0x000000018201a4d4 objc_exception_throw + 60
        2   AppKit                              0x00000001856a7368 -[NSApplication(NSEvent) _nextEventMatchingEventMask:untilDate:inMode:dequeue:] + 2844
        3   widgets                             0x00000001050c9348 _glfwPlatformPollEvents + 152
        4   widgets                             0x00000001050c1b80 glfwPollEvents + 48
        5   widgets                             0x0000000104e58c88 igRunLoop + 252
        6   widgets                             0x0000000104d3646c runtime.asmcgocall.abi0 + 124
)
libc++abi: terminating due to uncaught exception of type NSException
SIGABRT: abort
PC=0x18236c764 m=5 sigcode=0
signal arrived during cgo execution

goroutine 35 [syscall]:
runtime.cgocall(0x104e4d6e4, 0x14000235ee8)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/cgocall.go:157 +0x44 fp=0x14000235eb0 sp=0x14000235e70 pc=0x104cd3cb4
github.com/AllenDang/cimgui-go._Cfunc_igRunLoop(0x142e4d090, 0x104e113f4, 0x104e11440, 0x104e1148c, 0x104e11524)
        _cgo_gotypes.go:29012 +0x30 fp=0x14000235ee0 sp=0x14000235eb0 pc=0x104d8fcd0
github.com/AllenDang/cimgui-go.(*GLFWBackend).Run.func1(0x1?)
        /Users/allen/go/pkg/mod/github.com/!allen!dang/cimgui-go@v0.0.0-20230918114712-675654f053d9/glfw_backend.go:251 +0xa4 fp=0x14000235f50 sp=0x14000235ee0 pc=0x104d98ac4
github.com/AllenDang/cimgui-go.(*GLFWBackend).Run(0x0?, 0x0?)
        /Users/allen/go/pkg/mod/github.com/!allen!dang/cimgui-go@v0.0.0-20230918114712-675654f053d9/glfw_backend.go:251 +0x40 fp=0x14000235f70 sp=0x14000235f50 pc=0x104d989f0
main.main.(*MasterWindow).Run.func1()
        /Users/allen/Documents/Gocode/src/github.com/AllenDang/giu/MasterWindow.go:241 +0xe4 fp=0x14000235fa0 sp=0x14000235f70 pc=0x104e10894
github.com/faiface/mainthread.Run.func1()
        /Users/allen/go/pkg/mod/github.com/faiface/mainthread@v0.0.0-20171120011319-8b78f0a41ae3/mainthread.go:37 +0x30 fp=0x14000235fd0 sp=0x14000235fa0 pc=0x104dfe100
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x14000235fd0 sp=0x14000235fd0 pc=0x104d36674
created by github.com/faiface/mainthread.Run in goroutine 1
        /Users/allen/go/pkg/mod/github.com/faiface/mainthread@v0.0.0-20171120011319-8b78f0a41ae3/mainthread.go:36 +0xbc

goroutine 1 [select, locked to thread]:
runtime.gopark(0x14000054ea8?, 0x2?, 0xa0?, 0x21?, 0x14000054e94?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:398 +0xc8 fp=0x14000054d40 sp=0x14000054d20 pc=0x104d07a28
runtime.selectgo(0x14000054ea8, 0x14000054e90, 0x0?, 0x0, 0x2?, 0x1)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/select.go:327 +0x608 fp=0x14000054e50 sp=0x14000054d40 pc=0x104d181f8
github.com/faiface/mainthread.Run(0x1400011e318)
        /Users/allen/go/pkg/mod/github.com/faiface/mainthread@v0.0.0-20171120011319-8b78f0a41ae3/mainthread.go:42 +0x110 fp=0x14000054ed0 sp=0x14000054e50 pc=0x104dfe0a0
github.com/AllenDang/giu.(*MasterWindow).Run(...)
        /Users/allen/Documents/Gocode/src/github.com/AllenDang/giu/MasterWindow.go:233
main.main()
        /Users/allen/Documents/Gocode/src/github.com/AllenDang/giu/examples/widgets/widgets.go:269 +0x170 fp=0x14000054f30 sp=0x14000054ed0 pc=0x104e10780
runtime.main()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:267 +0x2bc fp=0x14000054fd0 sp=0x14000054f30 pc=0x104d075fc
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x14000054fd0 sp=0x14000054fd0 pc=0x104d36674

goroutine 2 [force gc (idle)]:
runtime.gopark(0x0?, 0x0?, 0x0?, 0x0?, 0x0?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:398 +0xc8 fp=0x14000044f90 sp=0x14000044f70 pc=0x104d07a28
runtime.goparkunlock(...)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:404
runtime.forcegchelper()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:322 +0xb8 fp=0x14000044fd0 sp=0x14000044f90 pc=0x104d078b8
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x14000044fd0 sp=0x14000044fd0 pc=0x104d36674
created by runtime.init.6 in goroutine 1
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:310 +0x24

goroutine 18 [GC sweep wait]:
runtime.gopark(0x0?, 0x0?, 0x0?, 0x0?, 0x0?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:398 +0xc8 fp=0x14000040760 sp=0x14000040740 pc=0x104d07a28
runtime.goparkunlock(...)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:404
runtime.bgsweep(0x0?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgcsweep.go:280 +0xa0 fp=0x140000407b0 sp=0x14000040760 pc=0x104cf3840
runtime.gcenable.func1()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgc.go:200 +0x28 fp=0x140000407d0 sp=0x140000407b0 pc=0x104ce85a8
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x140000407d0 sp=0x140000407d0 pc=0x104d36674
created by runtime.gcenable in goroutine 1
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgc.go:200 +0x6c

goroutine 19 [GC scavenge wait]:
runtime.gopark(0x1400008e000?, 0x105124ee0?, 0x1?, 0x0?, 0x140000824e0?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:398 +0xc8 fp=0x14000040f50 sp=0x14000040f30 pc=0x104d07a28
runtime.goparkunlock(...)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:404
runtime.(*scavengerState).park(0x1052f8fa0)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgcscavenge.go:425 +0x5c fp=0x14000040f80 sp=0x14000040f50 pc=0x104cf10bc
runtime.bgscavenge(0x0?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgcscavenge.go:653 +0x44 fp=0x14000040fb0 sp=0x14000040f80 pc=0x104cf1614
runtime.gcenable.func2()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgc.go:201 +0x28 fp=0x14000040fd0 sp=0x14000040fb0 pc=0x104ce8548
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x14000040fd0 sp=0x14000040fd0 pc=0x104d36674
created by runtime.gcenable in goroutine 1
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mgc.go:201 +0xac

goroutine 34 [finalizer wait]:
runtime.gopark(0x8?, 0x10518a880?, 0x1?, 0x45?, 0x104d450e4?)
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/proc.go:398 +0xc8 fp=0x14000044580 sp=0x14000044560 pc=0x104d07a28
runtime.runfinq()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mfinal.go:193 +0x108 fp=0x140000447d0 sp=0x14000044580 pc=0x104ce7698
runtime.goexit()
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/asm_arm64.s:1197 +0x4 fp=0x140000447d0 sp=0x140000447d0 pc=0x104d36674
created by runtime.createfing in goroutine 1
        /opt/homebrew/Cellar/go/1.21.1/libexec/src/runtime/mfinal.go:163 +0x80

r0      0x0
r1      0x0
r2      0x0
r3      0x0
r4      0x182360647
r5      0x16d151c80
r6      0x6e
r7      0x3
r8      0xb7c7c141955a3bf8
r9      0xb7c7c140f84f0bf8
r10     0x200
r11     0xb
r12     0xb
r13     0x1ff800
r14     0x7fb
r15     0x85635016
r16     0x148
r17     0x1e1f4b3a0
r18     0x0
r19     0x6
r20     0x16d153000
r21     0x1803
r22     0x16d1530e0
r23     0x600000008f00
r24     0xffffffffffffffff
r25     0x133828048
r26     0x1400011e318
r27     0x1
r28     0x140000031e0
r29     0x16d151bf0
lr      0x1823a3c28
sp      0x16d151bd0
pc      0x18236c764
fault   0x18236c764
exit status 2