I can confirm [...] the effectiveness of the work-around "GTK_THEME=adwaita abiword".
With some more testing I have to qualify that statement a bit: With the adwaita theme the behaviour is clearly improved compared to the default. I have not seen text flickering so far. But the cursor still flickers a bit and sometimes disappears completely until some new text is entered.
I wrote:
I can confirm [...] the effectiveness of the work-around "GTK_THEME=adwaita abiword".
With some more testing I have to qualify that statement a bit: With the adwaita theme the behaviour is clearly improved compared to the default. I have not seen text flickering so far. But the cursor still flickers a bit and sometimes disappears completely until some new text is entered.