4.1

Fu-Bama wrote: Found that Dark style has alpha slider range above 1.0, so setting it to 1.0 gives semi-transparent UI

This is not a bug. The dark style has a background alpha of 240, which is why it is transparent. The "Global Alpha" value is multiplied on top of whatever the style set. If you want the dark style, but with an opaque background, select the dark style, then switch to the "Custom Advanced" style and change the alpha field of "WindowBg" to 255.

Fu-Bama wrote: Some issues spotted:
• It seems that version 4 loads all shaders despite performance mode (according to splash-screen at the beginning in DXGI x64)
• I don't know if above is the reason, but performance in 4.1.1 is slightly worse than 3.4.1

It loads all shaders, but only compiles the active ones to bytecode. It also only allocates and loads textures for those effects that are active (you can verify that on the Statistics page).
There is no garbage collection though: Once an effect is activated all resources will stay in memory even after deactivating it again. This is so that there is no hitch the next time the effect is toggled on, because all resources are already there. To fully unload all effects and textures again click the "Reload" button.

Fu-Bama wrote: Some feedback:
• Regarding user experience, colors settings in theme section feels overwhelming, like there are too many options.
• Changing size of the UI by Ctrl+ScrollWheel makes everything blurry, maybe transition between background and text should be half-pixel?
• Regarding text editor, using Shift+Arrow key works nice at selecting text, but Shift+Mouse drag does not, it would be a nice addition.

1) That's why the "Custom Simple" style exists.
2) The default font is optimized for a single size. Scaling it up or down will make it look bad. You'll have to use a custom font to keep things better looking when scaling the UI. Also the font renderer in ImGui is rather simple, so some blurring is to be expected. There is a branch which uses FreeType for font rasterization, but I don't see an advantage in increasing complexity and adding another dependency for this special case, when the default renderer works fine most of the time.
3) Done: github.com/crosire/reshade/commit/1ab974...aa568f39c25a21d12667

Fu-Bama wrote: • In Blender 2.79 typing anything in ReShade UI gives double input, like 'error' results in 'eerrrroorr'

Fixed: github.com/crosire/reshade/commit/e67f16...2907576f66483695a476

brussell wrote: -the GUI always switches to the last tab (About, DX9, DX11) after reloading. This should rather be the Home tab.

This is already fixed in 4.1.1.

Fu-Bama wrote: When text editor is opened and you switch to performance mode, name of the currently opened shader changes to some other one (experienced in OpenGL).

Can't reproduce that. The editor always deselects any shader and shows an empty window after reloading (e.g. by switching performance mode). This is because the effect IDs change after reloading so it is not safe to reference the text of an old one.

Fu-Bama wrote: But found another. When you right click on color value to change from RGB to HSV in DirectX9 it shows floating "Reset to default value" button. In UI color settings it works as expected.

This is explicitly disabled to keep the context menu consistent across all values. See github.com/crosire/reshade/blob/e2ee01fa...source/gui.cpp#L1813 > ImGuiColorEditFlags_NoOptions
Other option would be to allow that context menu, but that would remove the reset to default value option for color values.

It's not duplicated. The button above resets everything in that effect. The context menu only the specific value. ReShade never shows the RGB/HSV context menu on color values (only on a different UI page, namely the settings, which have no connection to effect values).