V4.50.19

[S.E. Mitchell]

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Windows version: 25 Dec 2025 v4.50.19
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https://semware.com/files/tse-pro-install/tse-setup-4.50.19.zip

isWinClipAvailable() was broken - did not return correct values,
especially when a column block from TSE was in the Windows
clipboard. Fixed. Reported by Zhong Zhao.

capture() of a shell command was broken. Fixed.

The About screen now has an estimate of how much memory is left.

Editor works on Win95/Win98 again.

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Linux version: 25 Dec 2025 v4.50.19
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https://semware.com/files/tse-pro-install/tse-linux-4.50.19.tgz
https://semware.com/files/tse-pro-install/tse-linux-4.50.19.zip

zip/tar extracts/creates a directory called "tse".

Made isWinClipAvailable() much faster and mostly hang-proof.
Thanks to Knud van Eeden for the code.