Cannot preview image defined by huge base64 string

[hsandt]

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Describe the bug
Typora stops previewing base64 images (e.g. from standalone HTML exports) when the strings get too long (that happens with a combination of a picture of big dimensions and a lot of details on the picture)

Here is the sample image I used:

If you're knowledgeable in base64 conversion you can do it yourself (personally I use base64 sample_image_1600x1000.png | xclip -selection clipboard on Linux), but I prepared a .md file so it's easier to just download it, see Sample Markdown File more below.

To Reproduce
Steps to reproduce the behavior:

1. Open the Sample Markdown File
2. See how the base64 string ![img](data:image/png;filename=red_square.png;base64,iVBO...) is displayed as raw text, no image preview

Expected behavior
Big pictures should be previewed, or, if Typora has a safeguard to avoid overflow exploits or app freeze, it should at least display a warning, either locally near the base64 string, or at the top right after pasting, using the existing warning system:

(taken from #4869)

Screenshots / Screencasts

Sample Markdown File
base64 huge string demo.md

Desktop (please complete the following information):

• OS: Linux Ubuntu 22.04

Typora Version
1.7.6

Additional context
I'm working with a lot of charts and one of them was very big, although the image very complex. The sample image I put represents that.

A pure red rectangle of 1600x1000 won't have the issue so I have to add colored details.