the undescent rendering of Matrices' square brackets

[idealkindom]

SumatraPDF version

• Version 3.6.16469 64bit
  Describe the bug
  All the square brackets can not be rendered as they should be, which could be rendered right in Koober reader, which is much heavier than Summatra.
  To Reproduce
  I attached the sample pdf to test the problem.
  Expected behavior
  The square brackest in the pdf should be rendered right.

File that reproduces the problem
I attached.

Screenshots
on the left is Summatra, while on the right is Koober, with the same pdf file.

63_PDFsam_mechanics basic problem.pdf

[GitHubRulesOK]

The brackets are not seen in my Adobe Acrobat nor a PDF editor.

It looks like something has been messing up fonts visibility and colours to try to emulate graphics rather than use large [ in LaTeX or a word processor SamBox is Apache Java ? and historically Java Fonts have a poor history of usage in PDF.

It failed to include the font and relies on a generic font name called "symbol"

[idealkindom]

The brackets are not seen in my Adobe Acrobat nor a PDF editor.

It looks like something has been messing up fonts visibility and colours to try to emulate graphics rather than use large [ in LaTeX or a word processor SamBox is Apache Java ? and historically Java Fonts have a poor history of usage in PDF.

It failed to include the font and relies on a generic font name called "symbol"

I tried some other pdf readers too, finding that many failed to render those brackets right. However, Koober reader dose it well.

[sergsako]

Brackets in this document are displayed well by Microsoft Edge 131.0.2903.63 (on Win10 21H2 x64) which, in its turn, uses some integrated components of Adobe Reader.