Ironically this technique was used in phishing for MS Office 365 credentials (users of which often use MS Outlook): https://www.avanan.com/blog/zerofont-phishin

Ironically this technique was used in phishing for MS Office 365 credentials (users of which often use MS Outlook): https://www.avanan.com/blog/zerofont-phishing-attack https://www.avanan.com/blog/zerofont-phishing-attack Rendering in Outlooks changes from time to time - it is worth to check if this workaround is still required.