I think that the usefulness of a gif in this forum or at least on boards where a certain level of penetration is required with the idea of an ON-TOPIC gif has great strength, but sometimes certain gifs in certain conversations are too unwise.
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Updates in any post sometimes go unnoticed when one makes quick reviews of readings to try to hit a good answer or find an update, so if you allow me I will include that.
I think that should be more the focus on giving weight to the post in its content.
Anyway, as far as you can, stay away from shitgifs in inappropriate places ... and watch out, I like shitgif / memes but they have their time and place.
I think the discussion would be to create a gallery of the forum in gifs or images that are available under the explanation of the OP to use, I think we all know today where the gifs are.
But useful gifs that can help us add value to our post require an additional plus that is not complex in reality to make them, in fact there are many websites that do it without resorting to any software, but getting the idea in that gifs is very staff depending on the case.
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The process in imgur.com is the same as the one mentioned in the OP.
You can change the dimensions by adding the following code:
img height=xxx
There are several associated topics in B&H.