Wrong cursor positioning when typing an Indic consonant cluster by inserting a virama

When writing a consonant cluster in an Indic script you have to create a <FirstConsonant,ViramaCharacter,SecondConsonant> sequence, which can result in a ligature graphically different from just the two characters one after all.
If you type the first consonant, then the virama, then the second consonant, the cursor behaves fine, ie. it get positioned after the created cluster. However if you type the first consonant, then the second consonant, then goes between the two consonants, then type the virama, the cursor remains in the middle of the cluster instead of going at the right, which can look quite weird and can be a little disturbing. If you use the arrows keys after that, the problem gets fixed.
Here are two examples with Devanagari script :

• type "त" (U+0924), then type "न" (U+0928), then go between the two, then type "्" (U+094D)
• type "ज" (U+091C), then type "ञ" (U+091E), then go between the two, then type "्" (U+094D)

I observed this bug with Devanagari, Gujarati and Tamil, so I guess it's the same for all Indic scripts.