Unicode characters and UI

[smartinventure]

Describe the bug
When using Unicode character like the "infinity symbol" gum gets confused about the length of the line

To Reproduce
Steps to reproduce the behavior:
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║ ♾️ TEST TOOLS ║
║ INSTALL MODE ║
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If you use this unicode character, you will see that in some terminals it is counted as a half or as a full character, which leads to the confusion.

Expected behavior
The frame does not "close" nicely, but has one of the vertical lines

"one column too early"

Screenshots