The source for the stroke5 table contains

    AUTO_SELECT = TRUE

I don’t think this is useful for the stroke5 input method,
it should be set to FALSE.

When set to TRUE, AUTO_SELECT does the following 4 quite unrelated things:

    1) commit the matched phrase and a line feed instead of the tabkeys
       and no line feed when Return is typed (apparently Chinese input
       methods like Wubi want to insert the tabkeys instead of the phrase
       on Return, this is used as a quick way to insert one Latin word
       without having to switch to direct input mode or another input
       method. But for non-Chinese input methods like the Russian
       “translit”, this makes of course no sense).
    
    2) commit the matched phrase when Tab is typed
    
    3) When committing by typing Space, commit the phrase followed by a
       “ ” instead of only the phrase.
    
    4) if typing a valid input character has the result that there are no
       candidates anymore, but there were candidates before typing that
       character, pop that character from the input again, commit the
       first of the previous candidates and then reprocess the input
       character.  This is also mainly needed for non-Chinese input
       methods like the Russian “translit”. The “translit” table
       contains:
    
         sh ш
         shh щ
    
       so typing “sh” matches “ш” and “щ”. The
       candidate with the shortest key sequence comes
       first in the lookup table, therefore “sh ш”
       is shown in the preëdit (The other candidate,
       “shh щ” comes second in the lookup table and
       could be selected using arrow-down. But
       “translit” hides the lookup table by default).
    
       Now, when after typing “sh” one types “s”,
       the key “shs” has no match, so add_input('s')
       returns “False” and we end up here. We pop the
       last character “s” which caused the match to
       fail, commit first of the previous candidates,
       i.e. “sh ш” and feed the “s” into the
       key event handler again.

So AUTO_SELECT = TRUE seems to be not useful for Chinese input methods
like stroke5.

In the long run, I should probably improve ibus-table to split
the hard to understand “AUTO_SELECT” option into several separate,
more easy to understand options. Like a separate option whether to pass
the space to the application when committing with space.