Character limit for a cell in Google Sheets

What is the character limit for a single cell in Google Sheets?

An answer in this forum mentioned it may be ~1 million.

What is the cell limit in Google Sheets?

We've increased the cell limit in Google Sheets from up to five million cells to up to ten million cells. This limit applies to new, existing, and imported files.

How do I add more than 255 characters in Excel?

Text values in formulas are limited to 255 characters. To create text values longer than 255 characters in a formula, use the CONCATENATE function or the concatenation operator (&).

While there may not have been a limit before when that forum was posted, today (July 2017) the limit is 50,000 characters. If you try to input 50,001 characters, you will get this error:

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