Bug on version 1.2.1 on post excerpts

Friends, I got a new bug with this new version 1.2.1, now with post excerpts.

Instead of explaining the bug, I shot two pictures that will show you what is happening. The difference between this two scenarios is ONLY the activation/deactivation of Optin Forms plugin. Note, with plugin activated the main page ignores post excerpts, what doesn’t happen when Optin Forms is disabled.
Just to reinforce, it didn’t happen with older versions of plugin.

Picture 1 – Optin Forms DISABLED
Picture 2 – Optin Forms ENABLED

https://ww.wp.xz.cn/plugins/optin-forms/