Comment 5 for bug 746892

SUCCESSFULLY DIAGNOSED, with WORKAROUND

Many thanks to Thomas Lübking for help diagnosing

This is due to an accessibility "feature" known as "slow keys"
*Somehow*, the feature gets randomly activated during normal use of the OS.
The normal user warning for this is a system bell (which may not be heard), so it's easy to miss; there is no graphical indicator of any sort.
Normally though, this feature should not be activated in the first place.

FIX / WORKAROUND:
- open the System Settings > Accessibility (or type "kcmshell4 access" in a terminal)
- under "[tab]Keyboard Filters" you may see Sticky Keys enabled if you are suffering from this; disable it and hit Apply
- to prevent this from happening again, go to "[tab]Activation Gestures", disable "Use gestures to activate...", set the inactivity timeout to the lowest possible setting (1min), and enable all the notification features

suggested severity: Highest (because it makes people's system unusable and they have no idea how to fix it)

how this should be fixed:
- source of random activation should be found and fixed
how this can be mitigated:
- kubuntu system settings should be set to those described in "FIX" to reduce chances of occurring
- KDE code can be modified to show a prominent accessibility status indicator, or require typing "confirm"

This is bug is suspected to be due to an Ubuntu configuration of either the base system or KDE packages, though I am unsure what might affect usability settings of all desktops.

(Maybe it's also possible that there exists some activation gesture which will cause a popup to appear, but the user will hit Enter while typing?)

go4linux's comment should also be investigated, because it may indicate this problem is also occurring in other desktop environments; if so that would help track down the cause of the random activations if it's the same issue