Revert "fix #903 Fixing paste on selectbox. Closes #904"

This reverts commit 0ebf3e51e68611c5d4b9939b19c51a0ae7ebbcbd.
Revert "fix #868 Introducing allowInvalidText property for Selectbox widget"

This reverts commit 7d4cf63be5a9ce9be653cdd02dc133de0ad3fcae.
v1.4.14