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This contains security optimizations and improvements.

• Add check for markdown service provider #66
• Add trumbowyg as a new editor option #78
• Use the validator and not the facade #80
• Center align notify-email container #88
• Preset the preheader in email view #85
• Add sidebar option to the discussion view #82
• Add HTML purifier for posts #84
• Fixed index endpoints to not expose user data #94

Thanks to the contributors for all the bug fixes! 🎉

• Delete .DS_Store files #73
• Vertically center align update action buttons #74
• Fix various grammar mistakes #75
• Fix XSS vulnerability #70
• Fix for integrity constraint issue caused by color column #71
• Fix loading resources #77
• Fix spelling #67

Minor fixes

• Title for category pages #62
• Responsive width for new_discussion form #61

Credits goes to @marzochi.