It's just happened to me again and I was able to collect some more details.
1. The play/pause media key on my keyboard can still be used to play/pause
the track.
2. The "Videos is not responding" popup appears over the Totem window when
I try to focus it.
3. I captured the following strace when I attempted to focus the window and
clicked "Wait" on the not responding popup. It doesn't look particularly
helpful:
restart_syscall(<... resuming interrupted poll ...>) = 0
unlink("/home/mac/.config/totem/session_state.xspf") = 0
lstat("/home/mac/.config/totem", {st_mode=S_IFDIR|0700, st_size=4096, ...})
= 0
lstat("/home/mac/.config", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat("/home/mac", {st_mode=S_IFDIR|0755, st_size=12288, ...}) = 0
lstat("/home", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat("/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
eventfd2(0, EFD_CLOEXEC|EFD_NONBLOCK) = 32
write(32, "\1\0\0\0\0\0\0\0", 8) = 8
write(6, "\1\0\0\0\0\0\0\0", 8) = 8
futex(0x7f4cb400dd20, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x7f4cb400dd20, FUTEX_WAIT_PRIVATE, 2, NULL) = -1 EAGAIN (Resource
temporarily unavailable)
futex(0x7f4cb400dd20, FUTEX_WAKE_PRIVATE, 1) = 0
futex(0x7f4cb400dcb0, FUTEX_WAKE_PRIVATE, 1) = 1
futex(0x55d55906a078, FUTEX_WAKE_PRIVATE, 1) = 1
poll([{fd=32, events=POLLIN}], 1, 25000) = 1 ([{fd=32, revents=POLLIN}])
read(32, "\1\0\0\0\0\0\0\0", 16) = 8
poll([{fd=32, events=POLLIN}], 1, 25000) = 1 ([{fd=32, revents=POLLIN}])
read(32, "\1\0\0\0\0\0\0\0", 16) = 8
write(32, "\1\0\0\0\0\0\0\0", 8) = 8
futex(0x55d55a1cac10, FUTEX_WAKE_PRIVATE, 2147483647) = 0
close(32) = 0
openat(AT_FDCWD, "/home/mac/.config/totem/session_state.xspf",
O_WRONLY|O_CREAT|O_EXCL, 0666) = 32
write(32, "<?xml version=\"1.0\" encoding=\"UT"..., 105) = 105
write(32, " <track>\n <location>file:///h"..., 147) = 147
write(32, " <title>BBC Radio 6 Music - Wi"..., 55) = 55
write(32, " <extension application=\"http:"..., 86) = 86
write(32, " <playing>true</playing>\n", 29) = 29
write(32, " </extension>\n", 16) = 16
write(32, " </track>\n", 11) = 11
write(32, " </trackList>\n</playlist>", 25) = 25
fstat(32, {st_mode=S_IFREG|0644, st_size=474, ...}) = 0
close(32) = 0
poll([{fd=3, events=POLLIN}, {fd=5, events=POLLIN}, {fd=10, events=POLLIN},
{fd=16, events=POLLIN}, {fd=18, events=POLLIN}, {fd=21, events=POLLIN}], 6,
9993 <detached ...>
4. I have the Media Player Indicator GNOME shell extension enabled. Its
play/pause button also continues to work whilst the main Totem UI is
unresponsive.
Mike.
