change http:// to ./ will cause SEGFAULT

I can't reproduce this locally (I get a "Midori can't find the page you're looking for" message saying the domain '.' can't be resolved). Can you get a backtrace or core dump from the crash?

Do
$ midori
and CTRL-SHIFT-Q to exit normally and clear any previous crash conditions.
Now do
$ strace midori ./play.google.com/

...
clock_gettime(CLOCK_MONOTONIC, {12814, 373355669}) = 0
poll([{fd=3, events=POLLIN}, {fd=8, events=POLLIN}, {fd=10, events=POLLIN}], 3, 0) = 1 ([{fd=3, revents=POLLIN}])
clock_gettime(CLOCK_MONOTONIC, {12814, 373723886}) = 0
fcntl64(38, F_SETLK64, {type=F_RDLCK, whence=SEEK_SET, start=1073741824, len=1}, 0xbfb24434) = 0
fcntl64(38, F_SETLK64, {type=F_RDLCK, whence=SEEK_SET, start=1073741826, len=510}, 0xbfb24434) = 0
fcntl64(38, F_SETLK64, {type=F_UNLCK, whence=SEEK_SET, start=1073741824, len=1}, 0xbfb24434) = 0
access("/home/jidanni/.cache/webkitgtk/applications/ApplicationCache.db-journal", F_OK) = -1 ENOENT (No such file or directory)
fstat64(38, {st_mode=S_IFREG|0644, st_size=3440640, ...}) = 0
_llseek(38, 24, [24], SEEK_SET) = 0
read(38, "\0\0\0\20\0\0\r \0\0\0\0\0\0\0\0", 16) = 16
fstat64(38, {st_mode=S_IFREG|0644, st_size=3440640, ...}) = 0
access("/home/jidanni/.cache/webkitgtk/applications/ApplicationCache.db-wal", F_OK) = -1 ENOENT (No such file or directory)
fstat64(38, {st_mode=S_IFREG|0644, st_size=3440640, ...}) = 0
fcntl64(38, F_SETLK64, {type=F_UNLCK, whence=SEEK_SET, start=0, len=0}, 0xbfb24474) = 0
--- SIGSEGV {si_signo=SIGSEGV, si_code=SEGV_MAPERR, si_addr=0x11} ---
+++ killed by SIGSEGV +++
Segmentation fault

That's a system-call trace, not a backtrace. Can you install gdb and run as "midori -g" or use gdb manually? Thanks.

The crash is caused by the adblock extension; line 262 of extensions/adblock/extension.vala indexes into "subdomains[cnt]" without verifying that the subdomains array actually contains cnt values. Should be a trivial fix. Thanks for the backtrace and bug report!