The following warning was shown in PHP Compatibility checks for PHP 7.4
FILE: .../mod/oublog/pluginfile.php
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FOUND 0 ERRORS AND 1 WARNING AFFECTING 1 LINE
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34 | WARNING | [x] Curly brace syntax for accessing array elements
| | and string offsets has been deprecated in PHP
| | 7.4. Found: $relativepath{0}
| | (PHPCompatibility.Syntax.RemovedCurlyBraceArrayAccess.Found)
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https://github.com/moodleou/moodle-mod_oublog/blob/5377524a308592f01e27bc54eaed2591d85b4cb3/pluginfile.php#L34
The following warning was shown in PHP Compatibility checks for PHP 7.4