I tried your ibus-pinyin ppa; the problem still persists.  I will explain
that in better detail later.  Basically, after 18.04 (no problem there),
ibus-pinyin fails to update the hierarchy of an "entered" word or phase in
the "candidate list".   This is one of the most important features of a
Chinese input tool.  Without it, thhis tool is unusable.

The Chinese Ubuntu forum member who helped testing ibus-libpinyin 1.11
(百草谷居--btw, he is also a CPA）mentioned two important features that are
lacking in ibus-libpinyin which actually also prevented him from using this
input tool (except for doing this test).  Both features are available (&
kicking) in ibus-pinyin.

However, my most critical concern is always about stability.  I have used
the same old ibus-pinyin Chinese input tool since 18.04 daily built first
became available and have not had any problem.  As I mentioned in previous
communications, for some unknown reason ibus-pinyin doesn't work well in
Fedora/RedHat (though it can be installed without any problem), in reasons
probably similar to why ibus-pinyin is not working well in 19.04/19.10.
This is the main reason that I am not too thrilled about Fedora.

On Wed, Jun 19, 2019 at 12:42 AM Gunnar Hjalmarsson <
<email address hidden>> wrote:

> Thanks Ping-Wu!
>
> Our attempts to recruit additional Chinese testers failed unfortunately.
> My view is that we still are ready to consider the proposed packages
> verified. I base my view on:
>
> * The bug reporter's test results according to comment #35
>
> * My own verification measures according to comment #23
>
> * The reporter of bug #1829947 expressed a positive testimony as to
>   the ibus-libpinyin version we are backporting here (comment #20 in
>   that report).
>
> * The proposed packages have 'matured' in -proposed for soon three
>   weeks.
>
> ** Tags removed: verification-needed verification-needed-bionic
> verification-needed-cosmic
> ** Tags added: verification-done verification-done-bionic
> verification-done-cosmic
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1768166
>
> Title:
>   Random crashes
>
> Status in ibus-libpinyin package in Ubuntu:
>   Fix Released
> Status in libpinyin package in Ubuntu:
>   Fix Released
> Status in ibus-libpinyin source package in Bionic:
>   Fix Committed
> Status in libpinyin source package in Bionic:
>   Fix Committed
> Status in ibus-libpinyin source package in Cosmic:
>   Fix Committed
> Status in libpinyin source package in Cosmic:
>   Fix Committed
>
> Bug description:
>   [Impact]
>
>   ibus-libpinyin has proved to crash far too often. One or more files in
>   ~/.cache/ibus/libpinyin get corrupted somehow, and emptying that
>   directory allows the user to keep using ibus-libpinyin.
>
>   In disco (and eoan) ibus-libpinyin 1.11.0 and libpinyin 2.2.2 are
>   present, and the number of crashes has been reduced significantly:
>
>   https://errors.ubuntu.com/?package=ibus-libpinyin&period=month
>
>   Upstream ChangeLog ibus-libpinyin:
>   ----------------------------------
>   version 1.11.0
>   * fixes keypad decimal
>   * fixes emoji candidates
>   * support configurable opencc config
>
>   version 1.10.92
>   * fixes Enter handling
>
>   version 1.10.91
>   * support ime.register_trigger in lua extension
>   * support predicted candidates
>   * support emoji input
>
>   version 1.10.0
>   * bug fixes
>
>   version 1.9.91
>   * migrate to use GSettings
>   * fixes lyx short cut issue
>
>   version 1.9.3
>   * translate input method name in ibus menu
>
>   Upstream ChangeLog libpinyin:
>   -----------------------------
>   version 2.2.2
>   * minor fixes
>
>   version 2.2.1
>   * fixes predicted candidates
>
>   version 2.2.0
>   * bug fixes
>
>   The proposal is to backport the disco versions of those packages to
>   bionic and cosmic in an attempt to prevent crashes. Proposed uploads
>   are available in this PPA:
>
>   https://launchpad.net/~gunnarhj/+archive/ubuntu/ibus-libpinyin
>
>   [Test Case]
>
>   * Install from {bionic,cosmic}-proposed:
>     - libpinyin13
>     - libpinyin-data
>     - ibus-libpinyin
>
>   * Use "Intelligent Pinyin" for typing and confirm that no new issues
>     show up when doing so.
>
>   (This is apparently not a confirmation that the upload really fixes
>   the bug. To compensate for that, we will await testing of the
>   -proposed packages by a few Chinese users before considering the
>   uploads verified.)
>
>   Reverse dependencies
>   --------------------
>   Besides ibus-libpinyin, also fcitx-libpinyin and ibus-libzhuyin depend
> on packages belonging to the libpinyin source package. So additional test
> measures are:
>
>   * Install fcitx-libpinyin and ibus-libzhuyin.
>
>   * Use both those tools for typing Chinese, and confirm that you don't
>     observe any adverse effects of the libpinyin upgrade.
>
>   [Regression Potential]
>
>   The changes are mostly bug fixes, so the regression risk should be
>   limited. Also consider that the starting point is a rather unstable
>   functionality.
>
>   NOTE TO SRU TEAM: Please let the SRU age for longer than 7 days to get
>   as much testing as possible. There do not seem to be too many risky
>   changes carried, but such jumps in upstream versions always carry some
>   regression-risk.
>
>   [Original description]
>
>   I have experienced random ibus-libpinyin crashes in bionic.  I cannot
>   reproduce it, but it occurred at least a few times, even after the
>   official bionic release.  Same crashes were also reported in the
>   Ubuntu Chinese forum.
>
>   Currently, the workaround is to delete the ~/.cache/ibus/libpinyin
>   folder.
>
>   I talked to Peng Wu, ibus-libpinyin's creator and main maintainer, he
>   suggested that we update the version of ibus-libpinyin to 1.10.
>
>   Can we give this update a trial?
>
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