It seems like you're trying to work around the lack of Bug 430465. If we had that, you might not feel the need for this. Spectacle isn't trying to be a general-purpose image editing tool, so overall I don't think letting people open existing images with it would make sense. There are other better image editing apps for that.

> It seems like you're trying to work around the lack of Bug 430465.

That's true: 430465 and current 442784 is two small but crucial features, that are missing from nowadays screenshot tool. So I finally bothered myself and reported them.

> If we had that, you might not feel the need for this.

If we had these functionalities, certainly I would not ask them, what we already have. But we don't have these in Spectacle and therefore I report them.

> Spectacle isn't trying to be a general-purpose image editing tool

That's true - Spectacle is far from image editing tool, even in general purpose. We have GIMP, Inkscape, etc for that. Spectacle is above all, screenshotting tool.

> so overall I don't think letting people open existing images with it would make sense.

It makes very much sense, if you are making screenshots. Quite often there could be copied any image and then there is a need to add e.g. steps onto it. For that, Spectacle has great feature. E.g. ICT teachers, like me, use that feature often, who prepare step-by-step tutorials.

> There are other better image editing apps for that.

Yes, as mentioned, GIMP, Inkscape, etc are these. But Shutter is great screenshotting tool, what Spectacle also could be, if to add those two small, but crucial features:
* crop feature in annotation tool;
* Copy Image from Clipboard, also drag and drop external image into Spectacle;

These small but crucial features doesn't make Spectacle anything, but still screenshot tool. 

Currently is very annoying to open GIMP (or whatever else) for cropping. Then getting image back to Spectacle is restricted due to inability to Copy Image from Clipboard (this is yet another scenario, why it would be useful). As we know, GIMP is quite heavy program compared with Spectacle.

Also is quite annoying to open image and make screenshot in first place - it would be much more logical to just drag-and-drop the image into Spectacle.

Then it happens, that I use something else, than Spectacle in order to achieve that smooth workflow. But this isn't what probably Spectacle's developers expect. Currently Spectacle could be replacement of Shutter under KDE, if those two small, but crucial features could be implemented.

Besides, Shutter is free and open-source software, it would be easy to look its source code (https://github.com/shutter-project/shutter) and copy its functionalities into Spectacle with appropriate adaption.

Besides, similar situation is with Skanlite - it lacks of scanning into PDF, including multipage PDF - https://bugs.kde.org/show_bug.cgi?id=299517 - it is reported already in 2012 - soon becomes 10 years already... Let's hope, that with Spectacle goes better. Besides, I was therefore forced to install Gtk-based Simple Scan (https://apps.gnome.org/et/app/simple-scan/) in KDE, where that scan to PDF, including multipage PDF is already implemented.

It's out of scope, sorry. Spectacle is a screenshot app, not a general purpose image editor. KDE already has a couple of those, such as Kolourpaint (basic) and Krita (advanced). If you like Spectacle's editing tools so much that you would like them in other image editing apps, then it would be good to do that, rather than turning Spectacle into something it isn't and can't be. :)

FWIW Gwenview and Koko can perform crop operations quickly and easily. I typically open a screenshot in one of those apps when I need to crop it after it's left Spectacle.

It seems that it is your way to "develop" app. I use screenshot tool Shutter then, which has that simple functionality. Sorry. Perhaps it was mistake to start use KDE - apps have missing functionality (Spectacle isn't the only one) and developers find excuses and refuse proposals. I used KDE3 last time and now some friends claimed KDE5 to be good one.

KDE has changed a lot since the KDE3 days. Back then the idea was to stuff every piece of functionality into every app. Today we embrace smaller leaner apps that do fewer things but do them better. We do still have a bunch of everything-and-the-kitchen-sink apps, but they tend to be professional-class productivity apps like Kile and KDevelop. Small utility apps like Spectacle don't benefit from overlapping in functionality too much with other apps.

I try to cope. I know the Linux philosophy about single purpose functionality. But just jumping between apps becomes overwhelming at some point, if you need do lots of screenshots and crop them. As currently it is needed to crop in external program, then getting cropped image back into Spectacle for annotations is tricky. This is why current issue was reported. It is just regular screenshotting tool workflow: create screenshot, crop, annotate, save or export to another app. Also repeat last screenshot. Nothing extra, which is inherent to more sophisticated graphics apps. Certainly it's your decision and actually I respect it, just described the screenshotting workflow, where two features are missing. If we could crop (#430465), then we could even survive without current Copy Image from Clipboard feature. Just the  complexity to get cropped image back to Spectacle is overwhelming especially in case of preparing teaching materials, where is need to create lot of screenshots quickly. I'd you need do only few screenshots, then it might not be an issue.

I understand. For what it's worth, we are hoping to add cropping into Spectacle's existing annotation toolset, so then you won't have to go into another app to do that in the first place. :)

FWIW I generally work around this by taking Rectangular Region screenshots that don't need to be cropped, rather than Full Screen screenshots that do. There is even a global shortcut to launch Spectacle and take a rectangular region screenshot (Meta+Shift+PrintScreen) which is super handy.

Thank you, I appreciate your efforts! This is definitely useful. But sometimes it is not possible to know, what area to select. E.g. I try to get screenshot from certain dialog or part of it, that will appear quickly into unpredictable place on screen. 

Then I would like to take even several screenshots but Spectacle keeps only one screenshot :( Also in case, where certain process is going on quite quickly that cannot be paused (e.g. installation) and I would like to take series of screenshots but I can't, as Spectacle keeps only one screenshot. I guess I need to file next feature request. 

Besides, Shutter does keep also previous screenshots as much as needed. I can also configure to them save automatically or not, also choose file format, location, etc. Now you can say again, that I want too much. Sorry, but Shutter has it and this is nothing extra, but belongs to basic screenshotting workflow.

Sorry of comparing with Shutter, but they really understood the workflow connected with screenshotting. As Shutter is also free and open-source software, then you can use their source code and don't need to write from scratch. In that way you can get features implemented quicker with less effort and use already reviewed code, that contains already less (if at all) bugs. This in turn can save time and efforts of hunting bugs, when to use already reviewed code. This is the power of free and open-source software.