With HW QWERTY spelling a predicted words leads to incorrect word accepted

Use WH Qwerty device (for example, E7 or E6) with Belle software (I don't have Anna for E7 so cannot say if it reproduces there as well).
If you are using E7, open the device keyboard.

Open any application with text editor (it doesn't matter if it is a QWidget-based, or QML one).
With word prediction active, type a word (for example: 'tadaa').
Press arrow down to pop up a word selection list.
Press "Spell" button.
Type 'radar' and press "Ok".
--> Editor content becomes 'radarTadaa' (i.e. typed word is not replaced, but newly spelled word is added to the beginning).

More complicated case fails somewhat more interestingly:
Open any application with text editor (it doesn't matter if it is a QWidget-based, or QML one).
With word prediction active, type a word 'world' and accept it by pressing arrow right.
Now move cursor just after 'w' of the accepted word and type 'tadaa'.
Press arrow down to pop up a word selection list.
Press "Spell" button.
Type 'radar' and press "Ok".
--> Editor content becomes 'radarWtadaaorld'

Looks like the spelled word is always added to the beginning of surrounded text.
And when spell popup is opened, the preedit text is already committed.