This plugin make format wrong

[naramoksu]

After I install this plugin. I found this works well. but this plugin break edit format. Text input box for description is not normal position. It seems some carriage return missing.

My environment is below
Environment:
Redmine version 3.4.6.stable
Ruby version 2.3.7-p456 (2018-03-28) [x86_64-linux]
Rails version 4.2.8
Environment production
Database adapter Mysql2
SCM:
Subversion 1.10.0
Cvs 1.12.13
Git 2.17.1
Filesystem
Redmine plugins:
clipboard_image_paste 1.12
redmine_custom_workflows 0.1.6
redmine_issue_templates 0.2.1
redmine_mentions 0.0.1
redmine_wiki_extensions 0.8.1

I'm looking for how to fix this. Please advice what to change.

Thanks in advance.