W3C Error on :break-word;

Hi

After updating our site to WordPress 5.1.1-de_CH, W3C Validator shows again 2 errors on line 1, column 89996 (word-break:break-word;overf) and on column 106630 (word-break:break-word;grid-). If I set the value :break-word; to :normal; on the two files “style-rtl.min.css” and “style.min.css” in /wp-includes/css/dist/block-library/ everything looks fine. The error is gone. But how does this affect the code within Gutenberg? Thanks for help.

Stephan

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