When using WebExecute TypeElement, I get $Failed if I have a diacritics character in the submitted string. Here is a minimal example:

session = StartWebSession["Chrome"];
WebExecute["OpenPage"->"https://stackoverflow.com/questions/35126293/how-to-set-text-into-textarea-with-selenium-webdriver"];
textArea = First@WebExecute["LocateElements"->"XPath"->"//*[@id=\"wmd-input\"]"];
WebExecute["TypeElement"->{textArea, "à"}]

If I change "à" to "a", it works so far so good.

[update] It's a bug, see work around in the link below.

[updade2] Bug solved in version 12.1.1

crosspost in Stack Exchange

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