Note: Possibly applicable to other versions.
Issue:
Depending on the particular implementation of the operating system, leading spaces may be stripped automagically by the system.
System:
Motorola e5 Play
Android 8.1
Zoiper Beta version 2.12.3
Steps to reproduce:
1. Launch Zoiper or open if already running.
2. Navigate to Settings -> Accounts -> [your account] -> Number Rewriting -> Dial strip characters.
3. Examine the list of characters to be stripped.
Expected Result:
The list of characters to be stripped begins with a space character.
Actual Result:
Depending on the particular O/S implementation, the leading space may be missing.
Workaround/suggested solution:
Embed the space between two other characters so that it's not at either the beginning or end of the list.
Viz.:
List as provided: ".-() []{}/" (note that there is no leading space)
One way of solving the problem: ".-() [ ]{}/" (note that I have added a space between the two square brackets.)