community/xterm: segfault when selecting text (363-r1)

Since updating to xterm-363-r1, I get segfaults after selecting text.

Previously this was ok; I don't know how to see which previous version was in use, but it was recent (is there a log?)

xterm-367 from upstream does not seem to be affected. Upstream doesn't have a commit history I can check or bisect for information about this bug.

I have some customisation in Xdefaults.

$ gdb --args xterm
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Reading symbols from xterm...
(No debugging symbols found in xterm)
(gdb) run
Starting program: /usr/bin/xterm
[Detaching after fork from child process 7621]

Program received signal SIGSEGV, Segmentation fault.
get_meta (p=p@entry=0x7ffff7a29120 "\n\n\n\n\n\n")
    at src/malloc/mallocng/meta.h:141
141     src/malloc/mallocng/meta.h: No such file or directory.
(gdb) bt
#0  get_meta (p=p@entry=0x7ffff7a29120 "\n\n\n\n\n\n")
    at src/malloc/mallocng/meta.h:141
#1  0x00007ffff7f8abe7 in __libc_free (p=0x7ffff7a29120)
    at src/malloc/mallocng/free.c:105
#2  0x00005555555794e2 in ?? ()
#3  0x000055555557af3c in ?? ()
#4  0x000055555557daba in ?? ()
#5  0x00007ffff7d9712f in ?? () from /usr/lib/libXt.so.6
#6  0x00007ffff7d974dc in ?? () from /usr/lib/libXt.so.6
#7  0x00007ffff7d97ff1 in _XtTranslateEvent () from /usr/lib/libXt.so.6
#8  0x00007ffff7d7971b in XtDispatchEventToWidget () from /usr/lib/libXt.so.6
#9  0x00007ffff7d79b3d in ?? () from /usr/lib/libXt.so.6
#10 0x00007ffff7d79cb1 in XtDispatchEvent () from /usr/lib/libXt.so.6
#11 0x00005555555a818d in ?? ()
#12 0x000055555558ba71 in ?? ()
#13 0x000055555558bcb1 in ?? ()
#14 0x0000555555577756 in ?? ()
#15 0x00007ffff7f83a03 in libc_start_main_stage2 (main=0x5555555767c0, argc=1,
    argv=0x7fffffffea18) at src/env/__libc_start_main.c:94
#16 0x0000555555577a1c in ?? ()
#17 0x0000000000000001 in ?? ()
#18 0x00007fffffffecc9 in ?? ()
#19 0x0000000000000000 in ?? ()
(gdb)

.Xdefaults:

xterm*background: Black
xterm*foreground: DarkGrey
xterm*cursorColor: Red
xterm*reverseVideo: false
xterm*scrollBar: false
xterm*reverseWrap: true
xterm*font: fixed
xterm*fullCursor: true
xterm*scrollTtyOutput: off
xterm*scrollKey: on
xterm*fastScroll: on
xterm*titleBar: false
xterm*iconName: xterm
xterm*activeIcon: false
xterm*title: xterm
xterm*colorULMode: off
xterm*colorBDMode: off
xterm*trimSelection: on
xterm*highlightSelection: on
!xterm*on3Clicks: regex [^ ''""()<>$+]*
xterm*on3Clicks: line
xterm*on4Clicks: line
xterm*on5Clicks: group
xterm*eightBitInput: false
xterm*metaSendsEscape: true
xterm*pointerMode: 0
xterm*allowColorOps: false
xterm*allowFontOps: false
xterm*allowTcapOps: false
xterm*allowTitleOps: false
xterm*allowWindowOps: false
xterm*utf8: true