Sogou IME (on Ubuntu): How to output pinyin with tone marks? I have Sogou Pinyin on Ubuntu and things work fine, but I haven't been able to figure out how to type Pinyin with tone marks, e.g. 'mǎ', etc.

I've looked into the settings but found no option like that. I've searched online (in Chinese) but results I get show that Windows Sogou has a very different, more comprehensive menu structure with more options. The Ubuntu version seems like a dumbed down version of that, nothing close.

I've tried typing U + Unicode, e.g. U+0101 for 'ā' but that's a hassle. Copying from an online tool is also cumbersome, I have to type a lot of tone marked pinyin.

Has anyone run into this issue?

Edit: Screenshot of Sogou Settings menu on Ubuntu.
I struggled for many months to work out how produce Pinyin with the tone marks.  Eventually I managed it by installing the Ubuntu ibus (Intelligent Input Bus - core) currently using version 1.5.11.  I also have ibus-pinyin installed but to get the Latin alphabet with the tone marks including ǖ ǘ ǚ ǜ as well as the normal ū ú ǔ ù and of course all the other vowels just by typing the tone number you also need to install ibus-m17n .  This has the input method Chinese Hanyu Pinyin(m17n) as just described and also tonepy(m17n) which gives you a nice trimmed down list of the simplified Chinese characters filtered by the tone number you type when you want to type the characters instead of the Pinyin.  Probably too late for the original questioner but this information is so difficult to find on-line I thought it was worth adding for future reference.