• Which version of Wavebox are you using? [e.g. 3.0.0]

3.1.2

• Which Operating System are you using? [e.g. Windows 10, Mac OSX 10, Ubuntu 14.04]

macOS 10.12.4

But the issue continues from older versions (WMail) under the older Mac OS X 10.11.x.

In inputting Japanese sentences, we Japanese use Japanese IME (Input Method Editor) to convert alphabets to Japanese (CJK) characters.
The main process is converting Hiragana (ひらがな; Phonogram) to Kanji (漢字; Chinese characters; ideogram), and we have the state of selecting Kanji candidates because many Kanji have same sounds.
We enter the state almost every time when we want to input a word.
The issue I reporting occurs during the state of selecting Kanji candidates.
After entering the conversion state provided by Japanese IME, we sometimes delete characters in order, for example, to fix typo.
Wavebox app prevent us to delete a last character which is inside the range of the conversion state in one stroke of backspace (delete) key, while the other situation we can do that in just one push of backspace.
We have to input two delete keys to delete the last character, which annoys us.