Description of problem: I have had this problem a long time. I at first thought this problem came with Firefox 3.x, or with Fedora 9 -> 11/12. I do not remember I had this problem in Fedora 9, so after that anyhow. When Firefox has been in use actively for several hours, typing into input fields with keyboard becomes untolerable slow (2 letters per second or slower). Restarting Firefox fixes the problem for some time until after some hours use it manifests again. I have used often a way, where I first type the text of my forum message in terminal window, then copy it to the clipboard and paste it to Firefox so I wouldn't have to restart the browser. PASTEing from the clipboard is as fast as always even if typing has become slow in Firefox. Later I started to use Thunderbird's "New Email"-form for this same purpose, because it has thesaurus. Then I noticed also Thunderbird is having this same bug, so I started to search problem elsewhere than from Firefox plugins. I haven't noticed the same in other application but Firefox and Thunderbird. I've spent I think several working days in total trying to find the problem by uninstalling all the extensions, plugins, starting fresh profiles, Googling around and in other ways trying to debug the problem. Version-Release number of selected component (if applicable): The latest SCIM-packages which were available from Fedora 12 repositories in 2010-04-23 scim v 1.4.9 scim-bridge v 0.4.16 (and other related scim-components) How reproducible: Always Steps to Reproduce: 1. Using Firefox or Thunderbird long(ish) time. 2. Typing something to any input field (chat forums, new email,....) 3. Typing is VERY slow, like one - two letters per second. However PASTEing from clipboard is as fast. Expected results: To have usable Firefox where typing in input fields is not a torture. Additional info: I started Thunderbird under gdb to see what it is doing when typing becomes slow. ($ thunderbird -g) TB became slow in typing. I typed many key presses to the buffer and interrupted thunderbird from gdb (^C): : bt #0 0x0000003b690d73c3 in select () at ../sysdeps/unix/syscall-template.S:82 #1 0x00007fffe4d68d62 in scim_bridge_messenger_receive_message (messenger= 0x7fffdf5c98d0, timeout=0x0) at scim-bridge-messenger.c:490 #2 0x00007fffe4d6bdb9 in scim_bridge_client_read_and_dispatch () at scim-bridge-client.c:1216 #3 0x00007fffe4d6d215 in scim_bridge_client_handle_key_event ( imcontext=<value optimized out>, key_event=0x7fffd0775920, consumed= 0x7fffffffd3e4) at scim-bridge-client.c:1738 #4 0x00007fffe4d66b2f in filter_key_event (imcontext= 0x7fffd3041080 [ScimBridgeClientIMContext], event=0x7fffcfa8ab30, consumed= 0x7fffffffd3e4) at scim-bridge-client-imcontext-gtk.c:159 #5 0x00007fffe4d66c02 in key_snooper (widget=<value optimized out>, event= 0x7fffcfa8ab30, data=<value optimized out>) at scim-bridge-client-imcontext-gtk.c:220 #6 0x0000003b7214bb7d in gtk_invoke_key_snoopers (event=0x7fffcfa8ab30) at gtkmain.c:1929 #7 IA__gtk_main_do_event (event=0x7fffcfa8ab30) at gtkmain.c:1614 #8 0x0000003b7105feac in gdk_event_dispatch (source=<value optimized out>, callback=<value optimized out>, user_data=<value optimized out>) at gdkevents-x11.c:2372 #9 0x0000003b6a83923e in g_main_dispatch (context=0x7ffff7d176d0) at gmain.c:1960 #10 IA__g_main_context_dispatch (context=0x7ffff7d176d0) at gmain.c:2513 So, I was wondering, I really do not need SCIM for anything, so I try to remove it. I removed all scim-pacakges. From /var/log/yum.log: Apr 23 23:40:03 Erased: scim-bridge-gtk Apr 23 23:40:04 Erased: scim-bridge-qt Apr 23 23:40:05 Erased: scim-qtimm Apr 23 23:40:06 Erased: scim-chewing Apr 23 23:40:07 Erased: scim-python-pinyin Apr 23 23:40:10 Erased: scim Apr 23 23:40:14 Erased: scim-python Apr 23 23:40:16 Erased: scim-bridge Apr 23 23:40:17 Erased: scim-hangul Apr 23 23:40:18 Erased: scim-rawcode Apr 23 23:40:19 Erased: scim-anthy Apr 23 23:40:20 Erased: scim-m17n Apr 23 23:45:26 Erased: scim-libs And rebooted the system. After this I haven't (seem to) had the problem anymore. I can now use Firefox without needing to restart it after few hours because slow typing. Haven't yet used Thunderbird so much that I could confirm the problem is vanished from that also, but the problem was so much the same, I suspect removing SCIM helped there also.
In the past we received a very similar bug report, see below: Bug 554025 - Text input in firefox becomes increasingly sluggish; an excessive number of scim messages are observed. I will push this to Fedora 12 updates soon. Please test the package provided below.
scim-bridge-0.4.16-5.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/scim-bridge-0.4.16-5.fc12
scim-bridge-0.4.16-5.fc12 has been pushed to the Fedora 12 testing repository. If problems still persist, please make note of it in this bug report. If you want to test the update, you can install it with su -c 'yum --enablerepo=updates-testing update scim-bridge'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/scim-bridge-0.4.16-5.fc12
scim-bridge-0.4.16-5.fc12 has been pushed to the Fedora 12 stable repository. If problems still persist, please make note of it in this bug report.