imagesx(): Argument #1 ($image) must be of type GdImage, bool given

[agoenks29D]

In raising this issue, I confirm the following (please check boxes):

• I have read and understood the Wiki. Especially deploy and configuration articles.
• I have checked that the bug I am reporting can be replicated, or that the feature I am suggesting isn't already present.
• I have checked the pull requests tab for existing solutions/implementations to my issue/suggestion.
• I realise that server-side connectors are provided by various contributors. The implementations are vary due to programming language features/limitations or other factors. Thus a particular connector may not implement, or partially implement, the API features.
• I realise that any changes in configuration options and/or plugin parameters affect the plugin behavior. I specified all the differences from defaults in details.

I use the following server-side connector (check one):

• PHP connector by servocoder
• Java connector by fabriceci
• Python3 Flask connector by jsooter
• Python3 Flask connector by stevelittlefish
• NodeJs connector by jlaustill and forestlake
• ASP.NET Core connector by sinanbozkus
• ASHX connector by richeflits
• Other (specified below)

My familiarity with the project is as follows (check one):

• I have never used the project.
• I have used the project briefly.
• I have used the project extensively, but have not contributed previously.
• I am an active contributor to the project.

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